
The National Center for Atmospheric Research (NCAR) is one of the world’s premier scientific institutions. With a strong focus on the atmospheric and related sciences we have an internationally recognized staff and research program dedicated to advancing knowledge, providing community-based resources, and building human capacity. In this Annual Report, and in the accompanying Laboratory Reports, I invite you to learn more about NCAR, see how we are collaborating internally and with the worldwide research community to drive advances in our understanding of fundamental processes in our atmosphere and how the atmosphere interacts with, and is influenced by, other components of the Sun-Earth system. This progress is being driven, in part, by new technologies and their effective utilization at NCAR, including: advanced observing facilities for field studies and the Sun, powerful high-performance computing capabilities, valuable research data sets that describe the state of the Sun-Earth system, and widely used state-of-the-science community models that are providing improved capabilities for predictions of weather (including catastrophic events), air quality, hydrology, climate variability and change, and space weather. Important educational and technology transfer activities at NCAR continue to encourage outstanding young scientists into the field and bring new research and technical achievements into the public and private sectors.
The material presented in this Report is only a small sampling of the activities and accomplishments going on across the center at NCAR over the past year and reflects the considerable efforts of Dr. Jim Hurrell who retired from NCAR and the NCAR Directorship in August 2018. Jim’s career-long commitment to NCAR’s scientific program and his commitment to building capacity across the breadth of NCAR’s activities as Director was appreciated by many across the Center.
Please enjoy this Annual Report as a snapshot of recent NCAR competencies, facilities, and scientific accomplishments. Highlights across the imperative activities at NCAR include investigations in geoengineering simulation that permit scientists to investigate strategies to limit atmospheric warming and reduce its side effects. Studies of storm clusters in North America that are likely to be larger and more intense as climate changes, posing widespread flooding risks across the region. Research indicating that the improvements in US air quality have slowed over recent years and that it may be increasingly difficult for the Nation to achieve its ozone pollution goals. Numerous field campaigns took place globally over the past year, of note we’ve worked with the community to study wildfire smoke plumes with far-reaching effects on weather, air quality and climate, and the processes of cloud formation over the Southern Ocean. Process studies such as these will be captured in parameterizations like those that have seen the development and deployment of Version 2 of the Coupled Earth System Model which includes WACCM-X – a climate model that goes to the edge of space and enabled the first investigation of CO2’s impacts on the whole atmosphere. Further away, new modeling efforts have sought to understand the origins of the Sun’s activity “seasons” that could lead to better prediction of the solar storms at the heart of the global space weather initiative. Data science in the atmospheric sciences is starting to explore sub-seasonal to seasonal forecasting in weather and watersheds as climate is changing. The latter providing a critical decision-making tool for water managers.
Finally, we greatly miss the presence of our colleague and friend in Michael Thompson, who passed away on October 15th. Michael, working closely with his worldwide network of collaborators, significantly advanced our understanding of the Sun’s interior before turning his talents to organizational management over the last decade at the University of Sheffield in the UK, at HAO as Director (2010-2014), as Deputy Director of NCAR (2014-2018), and Interim President of UCAR (2015-2016). Michael’s steady approach, his patience, attention to detail, and general thoughtfulness will be missed by many across the Center and the broader NCAR/UCAR family.
Please accept my sincere thanks for your ongoing support and hard work.
With best wishes for 2019,
Scott McIntosh
Using a sophisticated computer model, scientists have demonstrated for the first time that a new research approach to geoengineering could potentially be used to limit Earth’s warming to a specific target while reducing some of the risks and concerns identified in past studies, including uneven cooling of the globe.
The scientists developed a specialized algorithm for an Earth system model that varies the amount and location of geoengineering — in this case, injections of sulfur dioxide high into the atmosphere — that would in theory be needed, year to year, to effectively cap warming. They caution, however, that more research is needed to determine if this approach would be practical, or even possible, in the real world.
The findings from the new research, led by scientists from the National Center for Atmospheric Research (NCAR), Pacific Northwest National Laboratory (PNNL), and Cornell University, represent a significant step forward in the field of geoengineering. Still, there are many questions that need to be answered about sulfur dioxide injections, including how this type of engineering might alter regional precipitation patterns and the extent to which such injections would damage the ozone layer. The possibility of a global geoengineering effort to combat warming also raises serious governance and ethical concerns.
"This is a major milestone and offers promise of what might be possible in the future,” said NCAR scientist Yaga Richter, one of the lead authors. “But it is just the beginning; there is a lot more research that needs to be done."
Past modeling studies have typically sought to answer the question "What happens if we do geoengineering?" The results of those studies have described the outcomes — both positive and negative — of injecting a predetermined amount of sulfates into the atmosphere, often right at Earth's equator. But they did not attempt to specify the outcome they hoped to achieve at the outset.
In a series of new studies, the researchers turned the question around, instead asking, "How might geoengineering be used to meet specific climate objectives?"
"We have really shifted the question, and by doing so, found that we can better understand what geoengineering may be able to achieve," Richter said.
The research findings are detailed in a series of papers published in a special issue of the Journal of Geophysical Research – Atmospheres.
In theory, geoengineering — large-scale interventions designed to modify the climate — could take many forms, from launching orbiting solar mirrors to fertilizing carbon-hungry ocean algae. For this research, the team studied one much-discussed approach: injecting sulfur dioxide into the upper atmosphere, above the cloud layer.
The idea of combating global warming with these injections is inspired by history's most massive volcanic eruptions. When volcanoes erupt, they loft sulfur dioxide high into the atmosphere, where it's chemically converted into light-scattering sulfate particles called aerosols. These sulfates, which can linger in the atmosphere for a few years, are spread around the Earth by stratospheric winds, forming a reflective layer that cools the planet.
To mimic these effects, sulfur dioxide could be injected directly into the stratosphere, perhaps with the help of high-flying aircraft. But while the injections would counter global warming, they would not address all the problems associated with climate change, and they would likely have their own negative side effects.
For example, the injections would not offset ocean acidification, which is linked directly to carbon dioxide emissions. Geoengineering also could result in significant disruptions in rainfall patterns as well as delays in healing the ozone hole. Moreover, once geoengineering began, if society wanted to avoid a rapid and drastic increase in temperature, the injections would need to continue until mitigation efforts were sufficient to cap warming on their own.
There would also likely be significant international governance challenges that would have to be overcome before a geoengineering program could be implemented.
"For decision makers to accurately weigh the pros and cons of geoengineering against those of human-caused climate change, they need more information," said PNNL scientist Ben Kravitz, also a lead author of the studies. "Our goal is to better understand what geoengineering can do — and what it cannot."
For the new studies, the scientists used the NCAR-based Community Earth System Model with its extended atmospheric component, the Whole Atmosphere Community Climate Model. WACCM includes detailed chemistry and physics of the upper atmosphere and was recently updated to simulate stratospheric aerosol evolution from source gases, including geoengineering.
"It was critical for this study that our model be able to accurately capture the chemistry in the atmosphere so we could understand how quickly sulfur dioxide would be converted into aerosols and how long those aerosols would stick around," said NCAR scientist Michael Mills, also a lead author. "Most global climate models do not include this interactive atmospheric chemistry.”
The scientists also significantly improved how the model simulates tropical stratospheric winds, which change direction every few years. Accurately representing these winds is critical to understanding how aerosols are blown around the planet.
The scientists successfully tested their model by seeing how well it could simulate the massive 1991 eruption of Mount Pinatubo, including the amount and rate of aerosol formation, as well as how those aerosols were transported around the globe and how long they stayed in the atmosphere.
Then the scientists began to explore the impacts of injecting sulfur dioxide at different latitudes and altitudes. From past studies, the scientists knew that sulfates injected only at the equator affect Earth unevenly: over-cooling the tropics and under-cooling the poles. This is especially problematic since climate change is warming the Arctic at a faster rate. Climate change is also causing the Northern Hemisphere to warm more quickly than the Southern Hemisphere.
The researchers used the model to study 14 possible injection sites at seven different latitudes and two different altitudes — something never before tried in geoengineering research. They found that they could spread the cooling more evenly across the globe by choosing injection sites on either side of the equator.
Meeting multiple objectives
The researchers then pieced together all their work into a single model simulation with specific objectives: to limit average global warming to 2020 levels through the end of the century and to minimize the difference in cooling between the equator and the poles as well as between the northern and southern hemispheres.
They gave the model four choices of injection sites — at 15 degrees and 30 degrees North and South in latitude — and then implemented an algorithm that determines, for each year, the best injection sites and the quantity of sulfur dioxide needed at those sites. The model's ability to reformulate the amount of geoengineering needed each year, based on that year's conditions, also allowed the simulation to respond to natural fluctuations in the climate.
The model successfully kept the surface temperatures near 2020 levels against a background of increasing greenhouse gas emissions that would be consistent with a business-as-usual scenario. The algorithm’s ability to choose injection sites cooled the Earth more evenly than in previous studies, because it could inject more sulfur dioxide in regions that were warming too quickly and less in areas that had over-cooled.
However, by the end of the century, the amount of sulfur dioxide that would need to be injected each year to offset human-caused global warming would be enormous: almost five times the amount spewed into the air by Mount Pinatubo on June 15, 1991.
"The results demonstrate that it is possible to flip the research question that's been guiding geoengineering studies and not just explore what geoengineering does but see it as a design problem,” said Doug MacMartin, a scientist at Cornell and the California Institute of Technology. “When we see it in that light, we can then start to develop a strategy for how to meet society’s objectives."
In the current series of studies, adjusting the geoengineering plan just once a year allowed the researchers to keep the average global temperature to 2020 levels in a given year, but regional temperatures — as well as seasonal temperature changes — were sometimes cooler or hotter than desired. So next steps could include exploring the possibility of making more frequent adjustments at a different choice of injection locations.
The scientists are already working on a new study to help them understand the possible impacts geoengineering might have on regional phenomena, such as the Asian monsoons.
"We are still a long way from understanding all the interactions in the climate system that could be triggered by geoengineering, which means we don’t yet understand the full range of possible side effects," said NCAR scientist Simone Tilmes, a lead author. "But climate change also poses risks. Continuing research into geoengineering is critical to assess benefits and side effects and to inform decision makers and society."
The research was funded by the Defense Advanced Research Projects Agency and the National Science Foundation, NCAR's sponsor.
Any opinions, findings and conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the National Science Foundation or the Defense Advanced Research Projects Agency.
Titles:
Authors: B. Kravitz, D. MacMartin, M. J. Mills, J. H. Richter, and S. Tilmes
Co-authors: F. Vitt, J. J. Tribbia, J.-F. Lamarque
Journal: Journal of Geophysical Research – Atmospheres
Data access: All the data from the experiments are available on the Earth System Grid
at
https://www.earthsystemgrid.org/dataset/ucar.cgd.ccsm4.so2_geoeng.html
or
http://dx.doi.org/10.5065/D6X63KMM
and
https://www.earthsystemgrid.org/dataset/ucar.cgd.ccsm4.so2_ctl_fb.html
or
http://dx.doi.org/10.5065/D6PC313T.
Major clusters of summertime thunderstorms in North America will grow larger, more intense, and more frequent later this century in a changing climate, unleashing far more rain and posing a greater threat of flooding across wide areas, new research concludes.
The study, by scientists at the National Center for Atmospheric Research (NCAR), builds on previous work showing that storms are becoming more intense as the atmosphere is warming. In addition to higher rainfall rates, the new research finds that the volume of rainfall from damaging storms known as mesoscale convective systems (MCSs) will increase by as much as 80 percent across the continent by the end of this century, deluging entire metropolitan areas or sizable portions of states.
"The combination of more intense rainfall and the spreading of heavy rainfall over larger areas means that we will face a higher flood risk than previously predicted," said NCAR scientist Andreas Prein, the study's lead author. "If a whole catchment area gets hammered by high rain rates, that creates a much more serious situation than a thunderstorm dropping intense rain over parts of the catchment."
"This implies that the flood guidelines which are used in planning and building infrastructure are probably too conservative," he added.
The research team drew on extensive computer modeling that realistically simulates MCSs and thunderstorms across North America to examine what will happen if emissions of greenhouse gases continue unabated.
The study was published Nov. 20 in the journal Nature Climate Change. It was funded by the National Science Foundation, which is NCAR's sponsor, and by the U.S. Army Corps of Engineers.
Hourly rain rate averages for the 40 most extreme summertime mesoscale convective systems (MCSs) in the current (left) and future climate of the mid-Atlantic region. New research shows that MSCs will generate substantially higher maximum rain rates over larger areas by the end of the century if society continues a "business as usual" approach of emitting greenhouse gases . (©UCAR, Image by Andreas Prein, NCAR. This image is freely available for media & nonprofit use.)
Thunderstorms and other heavy rainfall events are estimated to cause more than $20 billion of economic losses annually in the United States, the study notes. Particularly damaging, and often deadly, are MSCs: clusters of thunderstorms that can extend for many dozens of miles and last for hours, producing flash floods, debris flows, landslides, high winds, and/or hail. The persistent storms over Houston in the wake of Hurricane Harvey were an example of an unusually powerful and long-lived MCS.
Storms have become more intense in recent decades, and a number of scientific studies have shown that this trend is likely to continue as temperatures continue to warm. The reason, in large part, is that the atmosphere can hold more water as it gets warmer, thereby generating heavier rain.
A study by Prein and co-authors last year used high-resolution computer simulations of current and future weather, finding that the number of summertime storms that produce extreme downpours could increase by five times across parts of the United States by the end of the century. In the new study, Prein and his co-authors focused on MCSs, which are responsible for much of the major summertime flooding east of the Continental Divide. They investigated not only how their rainfall intensity will change in future climates, but also how their size, movement, and rainfall volume may evolve.
Analyzing the same dataset of computer simulations and applying a special storm-tracking algorithm, they found that the number of severe MCSs in North America more than tripled by the end of the century. Moreover, maximum rainfall rates became 15 to 40 percent heavier, and intense rainfall reached farther from the storm's center. As a result, severe MCSs increased throughout North America, particularly in the northeastern and mid-Atlantic states, as well as parts of Canada, where they are currently uncommon.
The research team also looked at the potential effect of particularly powerful MCSs on the densely populated Eastern Seaboard. They found, for example, that at the end of the century, intense MCSs over an area the size of New York City could drop 60 percent more rain than a severe present-day system. That amount is equivalent to adding six times the annual discharge of the Hudson River on top of a current extreme MCS in that area.
"This is a warning signal that says the floods of the future are likely to be much greater than what our current infrastructure is designed for," Prein said. "If you have a slow-moving storm system that aligns over a densely populated area, the result can be devastating, as could be seen in the impact of Hurricane Harvey on Houston."
Advances in computer modeling and more powerful supercomputing facilities are enabling climate scientists to begin examining the potential influence of a changing climate on convective storms such as thunderstorms, building on previous studies that looked more generally at regional precipitation trends.
For the new study, Prein and his co-authors turned to a dataset created by running the NCAR-based Weather and Research Forecasting (WRF) model over North America at a resolution of 4 kilometers (about 2.5 miles). That is sufficiently fine-scale resolution to simulate MCSs. The intensive modeling, by NCAR scientists and study co-authors Roy Rasmussen, Changhai Liu, and Kyoko Ikeda, required a year to run on the Yellowstone system at the NCAR-Wyoming Supercomputing Center.
The team used an algorithm developed at NCAR to identify and track simulated MCSs. They compared simulations of the storms at the beginning of the century, from 2000 to 2013, with observations of actual MCSs during the same period and showed that the modeled storms are statistically identical to real MCSs.
The scientists then used the dataset and algorithm to examine how MCSs may change by the end of the century in a climate that is approximately 5 degrees Celsius (9 degrees Fahrenheit) warmer than in the pre-industrial era — the temperature increase expected if greenhouse gas emissions continue unabated.
Title: Increased rainfall volume from future convective storms in the US
Authors: Andreas F Prein, Changhai Liu, Kyoko Ikeda, Stanley B Trier, Roy M Rasmussen, Greg J Holland, Martyn P Clark
Journal: Nature Climate Change
After decades of progress in cleaning up air quality, U.S. improvements for two key air pollutants have slowed significantly in recent years, new research concludes. The unexpected finding indicates that it may be more difficult than previously realized for the nation to achieve its goal of decreased ozone pollution, scientists said.
"Although our air is healthier than it used to be in the 80s and 90s, air quality in the U.S. is not progressing as quickly as we thought," said National Center for Atmospheric Research (NCAR) scientist Helen Worden, a co-author. "The gains are starting to slow down."
The study, by an international team of researchers, analyzed extensive satellite and ground-based measurements of nitrogen oxides and carbon monoxide. They found that levels of pollutants that can contribute to the formation of ground-level ozone, or smog, have failed to continue a fairly steady decline as estimated by the U.S. Environmental Protection Agency.
"We were surprised by the discrepancy between the estimates of emissions and the actual measurements of pollutants in the atmosphere," added Zhe Jiang, the lead author of the study. "These results show that meeting future air quality standards for ozone pollution will be more challenging than previously thought."
Jiang, who conducted much of the research during a postdoctoral fellowship at NCAR, is now with the University of Science and Technology of China.
The study will be published next week in the Proceedings of the National Academy of Sciences. The research was funded primarily by NASA, the National Oceanic and Atmospheric Administration, the University of Colorado Boulder, and the National Science Foundation, which sponsors NCAR.
Nitrogen oxides and carbon monoxide contribute to the formation of ground-level ozone, a pollutant that is harmful to human health and the environment. Levels of the pollutants have declined significantly since passage of the 1970 Clean Air Act, which spurred development of emission-reducing technologies, such as catalytic converters on automobiles and low nitrogen oxide burners at power plants.
A number of cities and outlying areas in the United States, however, remain out of compliance with EPA standards for ozone, which the agency made more stringent in 2015.
EPA emission estimates are based on monitored readings or engineering calculations of pollutants emitted by vehicles, factories, or other sources.
To obtain a fuller picture of national pollution levels, Jiang and his co-authors turned to satellite instruments that measure levels of nitrogen oxides and carbon monoxide. They analyzed these atmospheric observations with advanced computer simulations and statistical analyses, both to quantify pollutant concentrations and to map their concentrations across the contiguous United States. They then corroborated their findings with observations from air quality monitoring stations that measure local pollution levels.
The results showed that emission reductions slowed down dramatically in the five-year period from 2011 to 2015 compared to 2005 to 2009. Whereas nitrogen oxide concentrations dropped by 7 percent yearly from 2005 to 2009, they declined by just 1.7 percent yearly from 2011 to 2015—a 76 percent slowdown. Those findings contrast with EPA emission inventories, which put the slowdown at only 16 percent during the same time period.
Similarly, the study showed that carbon monoxide levels have declined much more slowly in recent years.
The research team originally thought that emissions from Asia could be playing a role, but this was not supported by the data. The measurements showed that the slowdown in improved air pollution levels was particularly pronounced in the eastern United States, one of several signs that the pollutants were not coming in from overseas.
The authors concluded that some of the reasons for the discrepancy for nitrogen oxides may be:
The study concluded that the slowdown in carbon monoxide, which is largely emitted by cars, is likely due to the large gains that have already been achieved by equipping cars with three-way catalytic converters.
"As you become effective at controlling emissions from cars and power plants, the other sources become more important and there's less information about them," said co-author Brian McDonald, a scientist with the National Oceanic and Atmospheric Administration and the Cooperative Institute for Research in Environmental Sciences.
The authors said that follow-up research, combining EPA inventories with a new generation of increasingly sophisticated satellite instruments, would lead to a more detailed understanding about how pollution is changing in response to emission controls.
"The top-down satellite measurements and the inventories provide complementary data that will enable us to get better estimates of the emission sources," McDonald said. "It will be useful to learn more about why the discrepancies exist and why the trend toward better air quality is slowing down."
Title: Unexpected slowdown of US pollutant emission reduction in the last decade
Authors: Zhe Jiang, Brian C. McDonald, Helen Worden, John R. Worden, Kazuyuki Miyazaki, Zhen Qu, Daven K. Henze, Dylan B. A. Jones, Avelino F. Arellano, Emily V. Fischer, Liye Zhu, and K. Folkert Boersma
Journal: Proceedings of the National Academy of Sciences
This summer, a specially equipped airplane is flying above wildfires in Idaho and surrounding western states in the most comprehensive field campaign to date that is focused on smoke plumes in the western United States.
Scientists from the National Center for Atmospheric Research (NCAR) and partner organizations are supporting a major research effort to study how smoke can impact weather, air quality, and climate. The project, called the Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption, and Nitrogen (WE-CAN), is primarily funded by the National Science Foundation, NCAR's sponsor. Additional support comes from the National Oceanic and Atmospheric Administration and NASA.
"Fires are a major contributor to air pollution, especially in the western United States," said Frank Flocke, an NCAR atmospheric scientist on the campaign. Western wildfires, which have been increasing in size and frequency, can produce high amounts of smoke that is hazardous to human health and ecosystems. Wildfire smoke can alter local weather patterns and can also have profound effects on air quality, even far downwind of its origin.
While the effects of wildfire smoke have been traced thousands of miles downwind, researchers still do not know the full impact of smoke as it travels and evolves in the atmosphere, which could leave some places vulnerable. "Studying the development of these fire plumes will lead to better predictions of the impact of wildfires on air quality, weather, and climate," said Flocke.
The field campaign, which is based in Boise, Idaho, includes the largest payload ever installed on the National Science Foundation's C-130 aircraft, which is managed and operated by NCAR. Scientists are focusing on three key areas:
"We’re following the transport and transformation of the plume of gases and aerosols emitted by wildfires to understand the chemical changes they undergo over time, how their properties might vary, and what their impacts are on human health and the environment," said Sylvia Edgerton, a program director in the Division of Atmospheric and Geospace Sciences at the National Science Foundation.
Until now, researchers studying wildfire smoke have had to use data from multiple locations and wildfires. WE-CAN aircraft operations will entail approximately 120 flight hours from July 22 to August 31, returning with a sweeping dataset for researchers to mine through for years.
"We are going to triple the amount we know about smoke chemistry in western wildfires in a few weeks," said Emily Fischer, the principal investigator of WE-CAN and a professor at Colorado State University. “When you look at the comprehensiveness of the payload we have, there have been very few sampling opportunities in the field with this kind of combination of instruments.”
An interdisciplinary team of scientists from NCAR, CSU, the University of Wyoming, the University of Washington, the University of Colorado Boulder, and the University of Montana are participating in the project.
The four-engine C-130 is equipped with state-of-the-art instrumentation to capture samples of the atmosphere during flight. A total of 26 sampling instruments inside and outside the aircraft will measure aerosols, cloud particles, trace gases, and radiation in the smoke plume. Many of the instruments are accompanied by a scientist on the flight to monitor the samples as they are collected.
NCAR’s Earth Observing Laboratory is responsible for carrying out safe flight operations in the vicinity of the wildfires targeted by WE-CAN and also provides many of the measurement systems deployed in the project.
"This is the largest payload we have ever installed, both in the volume of instruments and the electricity needed to power them," said NCAR's Pavel Romashkin, the C-130 project manager on the campaign. A payload this big comes with new challenges, the first among them being keeping the instruments, scientists, and crew from overheating, he said. Preventing that sometimes means maneuvering to higher altitudes, where the atmosphere is cooler, for a little while.
While their colleagues are trying to stay cool on the plane, a larger team of scientists are following the flights from the ground, not only monitoring incoming data, but keeping an eye on changing weather and satellite imagery of the wildfires. To account for rapid change, flight plans can be altered mid-flight to keep the aircraft flying within the plumes for as long as possible.
“We won’t know how vigorous the fire will be, or how windy it will be," said Flocke, who has worked on many field campaigns around the world. "Decision-making in the aircraft is critical."
This month, an international team of scientists will head to the remote Southern Ocean for six weeks to tackle one of the region's many persistent mysteries: its clouds.
What they discover will be used to improve climate models, which routinely underestimate the amount of solar radiation reflected back into space by clouds in the region. Accurately simulating the amount of radiation that is absorbed or reflected on Earth is key to calculating how much the globe is warming.
The field campaign, called the Southern Ocean Clouds, Radiation, Aerosol Transport Experimental Study, or SOCRATES, could also help scientists understand the very nature of how clouds interact with aerosols — particles suspended in the atmosphere that can be from either natural or human-made sources. Aerosols can spur cloud formation, change cloud structure, and affect precipitation, all of which affect the amount of solar radiation that is reflected.
During the mission, which will run from mid-January through February, the scientists will collect data from a bevy of advanced instruments packed onboard an aircraft and a ship, both of which are specially designed for scientific missions.
"SOCRATES will allow for some of the best observations of clouds, aerosols, radiation, and precipitation that have ever been collected over the Southern Ocean," said Greg McFarquhar, a principal investigator and the director of the University of Oklahoma Cooperative Institute for Mesoscale Meteorological Studies (CIMMS). "These data will provide us with critical insight into the physics of cloud formation in the region, information we can use to improve global climate models."
The U.S. portion of SOCRATES is largely funded by the National Science Foundation (NSF).
“The Southern Ocean is famously remote and stormy and it's hard to imagine a worse place to do a field campaign. But a vast, stormy ocean is a great laboratory for studying clouds, and it's clear from our models that we have a lot to learn about them,” said Eric DeWeaver, program director for Climate and Large-Scale Dynamics in NSF’s Geoscience directorate.
"I'm excited about this campaign because I think it will answer some fundamental questions about clouds and their dependence on atmospheric conditions," DeWeaver said. "We'll be able to use this information to understand cloud behavior closer to home and how clouds are likely to adjust to changing climatic conditions."
Critical observing and logistical support for SOCRATES is being provided by the Earth Observing Laboratory (EOL) at the National Center for Atmospheric Research (NCAR). Other U.S. principal investigators are based at the University of Washington.
The Australian portion of SOCRATES is largely funded by the country's government through the Australian Marine National Facility, which is owned and operated by CSIRO.
McFarquhar and his colleagues think the reason that climate models are not accurately capturing the amount of radiation reflected by clouds above the Southern Ocean is because they may not be correctly predicting the composition of the clouds. In particular, the models may not be producing enough supercooled water — droplets that stay liquid even when the temperature is below freezing.
One possible explanation for the problem is the way models represent how clouds interact with aerosols, a process that affects the amount of supercooled water in a cloud. These representations were developed from atmospheric observations, largely in the Northern Hemisphere, where most of the world's population lives.
But the atmosphere over the Northern Hemisphere — even over the Arctic — contains many more pollutants, including aerosols, than the atmosphere over the Southern Ocean, which is relatively pristine.
"We don't know how appropriate the representations of these processes are for the Southern Hemisphere," McFarquhar said. "SOCRATES will give us an opportunity to observe these cloud-aerosol interactions and see how much they differ, if at all, from those in the Northern Hemisphere."
For the SOCRATES field campaign, observations will be taken from the NSF/NCAR High-performance Instrumented Airborne Platform for Environmental Research, or HIAPER, a highly modified Gulfstream V aircraft, and the R/V Investigator, an Australian deep-ocean research vessel.
"Much of what we currently know about Southern Ocean cloud, aerosol, and precipitation properties comes from satellite-based estimates, which are uncertain and have undergone few comparisons against independent data," said co-investigator Roger Marchand, a scientist at the University of Washington. "The data collected during SOCRATES will also enable us to evaluate current satellite data over the Southern Ocean, as well as potentially help in the design of better satellite-based techniques."
The research aircraft will be based out of Hobart, Tasmania, and will make about 16 flights over the Southern Ocean during the course of the campaign. The many high-tech instruments on board will measure the size and distribution of cloud droplets, ice crystals, and aerosols, as well as record the temperature, winds, air pressure, and other standard atmospheric variables.
The instruments include NCAR's HIAPER Cloud Radar (HCR) and High Spectral Resolution Lidar (HSRL). The wing-mounted HCR is able to "see" inside clouds and characterize the droplets within, while the HSRL can measure air molecules and aerosols. Together, the two highly advanced instruments will give scientists a more complete picture of the wide range of particles in the atmosphere above the Southern Ocean.
The nature of the research — flying a plane in search of supercooled water —presents some challenges with aircraft icing.
"Oftentimes, the cleaner the air, the more probable large drops and severe icing conditions become," said Cory Wolff, the NCAR project manager who is overseeing aircraft operations for SOCRATES. "We have a number of precautions we're taking to mitigate that risk."
First, a mission coordinator whose sole job is to monitor icing conditions will join each flight. Second, the design of the flights themselves will help the crew anticipate icing conditions before they have to fly through them. On the flight south from Tasmania, the HIAPER GV will fly high above the clouds — and the icing danger. During that leg of the flight, the scientists will collect information about the clouds below, both with onboard radar and lidar as well as with dropsondes — small instrument packages released from the aircraft.
With that information, the scientists can determine whether it's safe to pilot the aircraft through the clouds on the return trip, collecting detailed information about the cloud composition.
The measurements taken from the sky will be complemented by data collected from instruments on board the Australian R/V Investigator, including the NCAR Integrated Sounding System. The ISS gathers extensive data by using a radar wind profiler, surface meteorology sensors, and a balloon-borne radiosonde sounding system. The team will launch soundings every six hours, and sometimes more often, throughout the campaign.
"Observations from the ship will help us understand the background state of the atmosphere — how it's behaving," said NCAR scientist Bill Brown, who traveled to Australia in late November to prepare the ISS for the voyage.
The ship will be deployed for the entire six weeks and will face its own challenges, notably the notorious roughness of the Southern Ocean, sometimes called the stormiest place on Earth.
"There are no land masses to break up the winds down there," Brown said. "So the ocean can be quite rough."
SOCRATES investigators will also draw on measurements from another Australian ship as it travels between Tasmania and Antarctica on resupply missions, the R/V Aurora Australis, as well as observations from buoys and some land-based instruments on Macquarie Island.
"I am excited that we will have such a comprehensive suite of observations," McFarquhar said. "If we just had the cloud observations we wouldn’t have the appropriate context. If we just had the aerosols and measurements below the clouds, we wouldn't be able to understand the complete picture."
For more about the SOCRATES campaign, visit the project website.
Australian Antarctic Division
Australian Bureau of Meteorology
Australian Department of Environment and Energy
Colorado State University
Cooperative Institute for Mesoscale Meteorological Studies
CSIRO
Karlsruhe Institute of Technology
Monash University
National Center for Atmospheric Research
National Science Foundation
NorthWest Research Associates
Queensland University of Technology
University of California San Diego
University of Colorado Boulder
University of Illinois at Urbana-Champaign
University of Melbourne
University of Oklahoma
University of Washington
The solar seasons — which change every six to 18 months from "bursty" to quiet, and vice versa — have been realistically simulated for the first time in a computer model of the Sun's shear layer beneath the turbulent outer shell, an advance that promises the ability to predict these seasonal fluctuations nearly a year in advance.
Solar seasons, discovered just a few years ago, are periods of greater or lesser solar activity. In what scientists have dubbed the bursty season, sunspots and the flares that can accompany them are more common. In the quiet season they are fewer and farther between.
These seasons are superimposed on the approximately 11-year solar cycle, when the Sun transitions from solar minimum (fewer sunspots) to solar maximum (more sunspots) and back again. The seasons serve to amplify — or dampen — the Sun's background state.
Now, scientists at the National Center for Atmospheric Research have simulated these seasons in a sophisticated solar model, discovering for the first time the physical mechanisms at their root. The new research, led by NCAR scientist Mausumi Dikpati, was published earlier this month in the Nature journal Scientific Reports.
Already, Dikpati and colleagues are working on using the model — fed with observations taken of magnetic fields on the front and back sides of the Sun — to make predictions of seasonal changes up to a year in advance. Such predictions are valuable because the major solar flares and coronal mass ejections that are more likely to occur during the bursty season can cause havoc on Earth, scrambling radio communications, damaging satellites, disabling power grids, and imperiling astronauts.
"Right now, space weather forecasters issue at most a one-day warning — sometimes just a few hours — that a coronal mass ejection might cause a damaging geomagnetic storm here on Earth," Dikpati said. "Having a model that captures the physical mechanisms behind the Sun's seasons can better equip scientists to forecast these storms."
In the new study, the scientists find that the solar seasons owe their origin to the interaction between two phenomena tied to the Sun's magnetic fields: Rossby waves and differential rotation.
Rossby waves, only recently discovered in observations of the Sun, are large-scale planetary waves that can also be found in Earth's atmosphere and oceans.
Differential rotation refers to the fact that the Sun's equator rotates more quickly than its poles. This difference allows the solar magnetic field to twist and tangle, sometimes combining into ropes of magnetic field lines that can burst from the Sun's surface.
Dikpati and her colleagues found that when the Rossby waves are tilted in a particular direction, they can feed on energy from the Sun's differential rotation. Once the Rossby waves have extracted all the available energy, the waves begin to straighten and feed energy back to the differential rotation, eventually tilting to the opposite direction. Then the cycle repeats.
This back-and-forth exchange of energy marks the changing of the solar seasons. The Sun's bursty season coincides with the period when Rossby waves have their maximum energy. During these times, the Rossby waves deform the surface of the Sun’s shear layer into bulges and depressions. When the bulges coincide with a rope of magnetic field lines, they provide an opportunity for those magnetic field lines to more easily break through the Sun's surface, often creating flares and coronal mass ejections, including very strong ones that affect Earth.
Bursty seasons — no matter whether they occur during a solar cycle that is stronger or weaker than normal — contain the most dangerous space weather events. For example, one of the strongest solar storms ever observed was generated in July 2012 during the current solar cycle, which is considered weak. The solar storm narrowly missed hitting Earth. If it had, solar scientists say that the impact on our modern, technology-driven society could have been devastating.
"The Sun is remarkably complex, and this modeling effort has given us some insight into the structures of the seemingly chaotic magnetic field," Dikpati said. "More complex modeling, with assimilation of more observations, will allow us to continue to work on improving prediction of dangerous solar storms."
The research was funded by the National Science Foundation, NCAR's sponsor. The model simulations for the study were run on both the Yellowstone and Cheyenne supercomputers at the NCAR-Wyoming Supercomputing Center. Other co-authors of the study are Paul Cally (Monash University Clayton in Australia), Scott McIntosh (NCAR), and Eyal Heifetz (Tel Aviv University in Israel).
A new team has formed to work with Dikpati on using the model for prediction. The team includes Yuhong Fan, Scott McIntosh, Lisa Upton, Jeff Anderson, and Nancy Collins (all of NCAR); Aimee Norton (Stanford University); Marty Snow (University of Colorado Boulder); and Doug Biesecker (National Oceanic and Atmospheric Administration.)
Title: The Origin of the "Seasons" in Space Weather
Authors: Mausumi Dikpati, Paul S. Cally, Scott W. McIntosh, and Eyal Heifetz
Journal: Scientific Reports, DOI: 10.1038/s41598-017-14957-x
The National Center for Atmospheric Research (NCAR) has released an updated version of its flagship climate model to include a host of new capabilities — from a much more realistic representation of Greenland's evolving ice sheet to the ability to model in detail how crops interact with the larger Earth system to the addition of wind-driven waves on the model's ocean surface.
The Community Earth System Model version 2 (CESM2) is an open-source community computer model largely funded by the National Science Foundation, which is NCAR's sponsor, and the U.S. Department of Energy's Office of Science.
Released publicly last week, CESM2 builds on a succession of climate models, each cutting edge for their day, stretching back decades to a time when their software only simulated atmospheric circulation. By comparison, CESM2 includes interactions among the land, ocean, atmosphere, land ice, and sea ice, representing the many important ways the different parts of the Earth system interact.
"The breadth of the science questions we can tackle just significantly expanded; that's very exciting to me," said Jean-François Lamarque, who led the effort to develop CESM2 until recently. "Every time we release a new model we're providing a better tool to do the science. It's a more complicated tool, but the world is very complicated."
The new capabilities of CESM2 include:
A full list of updates with more technical descriptions can be found at http://www.cesm.ucar.edu/models/cesm2/whatsnew.html.
Work on CESM2 began in earnest about five years ago, but scientists began tinkering with how to improve the model as soon as CESM1 was released in 2010. It's no different with CESM2.
"We've already started to think about what we can improve for CESM3," Lamarque said. "We know, for example, that we want to make the ocean model better to expand the kind of scientific questions it can be used to answer."
Collaboration and input from the broader Earth system science community has always been at the heart of the complex model development facilitated by NCAR. For example, the land model component of the new CESM2 tapped the expertise of more than 50 researchers at 16 different institutions.
CESM, which is freely available, is an important tool for Earth system science researchers across the United States and the globe who are studying everything from the predictability of seasonal droughts to accelerating sea level rise. The NCAR-based model is one of about a dozen leading climate models around the globe that scientists use to research the changing climate and contribute what they find to the Intergovernmental Panel on Climate Change.
Because the Earth system is so complicated, and computing resources are so limited, the computer models used to simulate how Earth's climate behaves use a mix of equations that actually represent the physics, biology, and chemistry behind the processes that unfold in the Earth system — from evaporation to ozone formation to deforestation to sea ice melt — and "parameterizations," which simplify small-scale processes and estimate their impacts.
"CESM2 is representing much more of the physics than past models, and we are doing a much better job of it," said CESM Chief Scientist Gokhan Danabasoglu, who is now leading the model development effort. "There are numerous new capabilities in all component models as well as significant infrastructure improvements for flexibility and easier portability.”
These improved equations allow the model to do an even better job replicating the real world.
"The model is our lab — the only laboratory we get when studying the climate," Lamarque said. "So it has to be close enough to the real world to be relevant."
As the atmosphere approaches the edge of space, it behaves very differently than it does closer to the surface, where weather takes place. For one thing, while the lower atmosphere warms in response to emissions of carbon dioxide (CO2), the outer and less dense atmosphere cools, radiating heat out into space.
Scientists have understood this for years, drawing on their knowledge of the physics and chemistry of the atmosphere and analysis of far-flung observations by satellites and other instruments. Now, in a major advance for computer modeling of the Earth system, they have captured these complex temperature changes in a simulation of the entire atmosphere.
"We now have a comprehensive picture that is largely in accord with the observations," said NCAR scientist Stan Solomon, the lead author of the new study. "By successfully modeling the whole atmosphere, we have demonstrated that advanced numerical simulations can describe the complexity of the layers of the atmosphere and how they influence one another."
Solomon and a team of NCAR scientists recently published their results in Geophysical Research Letters. The research was funded by the National Science Foundation, which is NCAR's sponsor, and by NASA.
CO2 molecules act as a greenhouse gas in the lower atmosphere, intercepting infrared radiation from the Earth's surface and, through collisions with other molecules, heating the atmosphere. Higher in the stratosphere and beyond however, molecules are more widely distributed, so collisions are far less frequent. In this thinner air, carbon dioxide molecules radiate the heat out to space, cooling the surrounding region.
To produce a simulation of the entire atmosphere's response to CO2, the research team turned to an advanced NCAR-based computer model: the extended version of the Whole Atmosphere Community Climate Model, or WACCM-X. The model represents the atmosphere from the planet's surface to the top of the thermosphere, more than 300 miles up, calculating temperature, density, wind, electric fields, and other variables, in three dimensions.
By representing the entire atmosphere in a single model, WACCM-X enables scientists to better understand how the different regions of the atmosphere interact with each other. They are conducting ongoing research, for example, into the ways hurricanes and other major storms near the surface send energy upward, potentially affecting the electric fields of the outer atmosphere that are important for communications and navigation systems.
"The trend in weather and climate modeling is to extend the models to higher and higher altitudes, so you're not neglecting processes that might have some effect on the big picture," Solomon said.
To put WACCM-X through its paces, Solomon and his colleagues simulated the influence of CO2 on the whole atmosphere, focusing on the period from 1974 to 2003. The simulations were run on at the NCAR-Wyoming Supercomputing Center in Cheyenne.
The results showed that, over a 30-year period under low solar activity conditions, the lowest level in the atmosphere (the troposphere) warms by about 1-2 degrees Fahrenheit. But cooling take place throughout much of the higher atmosphere, with temperatures dropping by as much as 15 degrees F in the thermosphere.
In addition to demonstrating the success of WACCM-X in simulating complex interactions across various levels of the atmosphere, this type of simulation can be important for monitoring space debris. Discarded satellite parts and rocket boosters that orbit high above Earth pose a hazard to active satellites. Their orbital paths are affected by atmospheric drag, and lower densities lead to longer orbital lifetimes and more space debris, especially when the Sun is less active.
"Understanding the density is important to satellite tracking," Solomon said. "There's a concern that a quiet Sun and reduced density in the upper atmosphere can work together, creating an environment that becomes particularly difficult for orbital navigation."
Title: Whole Atmosphere Simulation of Anthropogenic Climate Change
Authors: Stanley C. Solomon, Han-Li Liu, Daniel R. Marsh, Joseph M. McInerney, Liying Qian, and Francis M. Vitt
Journal: Geophysical Research Letters
How will weather change in the future? It's been remarkably difficult to say, but researchers are now making important headway, thanks in part to a groundbreaking new data set at the National Center for Atmospheric Research (NCAR).
Scientists know that a warmer and wetter atmosphere will lead to major changes in our weather. But pinning down exactly how weather — such as thunderstorms, midwinter cold snaps, hurricanes, and mountain snowstorms — will evolve in the coming decades has proven a difficult challenge, constrained by the sophistication of models and the capacity of computers.
Now, a rich, new data set is giving scientists an unprecedented look at the future of weather. Nicknamed CONUS 1 by its creators, the data set is enormous. To generate it, the researchers ran the NCAR-based Weather Research and Forecasting model (WRF) at an extremely high resolution (4 kilometers, or about 2.5 miles) across the entire contiguous United States (sometimes known as "CONUS") for a total of 26 simulated years: half in the current climate and half in the future climate expected if society continues on its current trajectory.
The project took more than a year to run on the Yellowstone supercomputer at the NCAR-Wyoming Supercomputing Center. The result is a trove of data that allows scientists to explore in detail how today's weather would look in a warmer, wetter atmosphere.
CONUS 1, which was completed last year and made easily accessible through NCAR's Research Data Archive this fall, has already spawned nearly a dozen papers that explore everything from changes in rainfall intensity to changes in mountain snowpack.
"This was a monumental effort that required a team of researchers with a broad range of expertise — from climate experts and meteorologists to social scientists and data specialists — and years of work," said NCAR senior scientist Roy Rasmussen, who led the project. "This is the kind of work that's difficult to do in a typical university setting but that NCAR can take on and make available to other researchers."
Other principal project collaborators at NCAR are Changhai Liu and Kyoko Ikeda. A number of additional NCAR scientists lent expertise to the project, including Mike Barlage, Andrew Newman, Andreas Prein, Fei Chen, Martyn Clark, Jimy Dudhia, Trude Eidhammer, David Gochis, Ethan Gutmann, Gregory Thompson, and David Yates. Collaborators from the broader community include Liang Chen, Sopan Kurkute, and Yanping Li (University of Saskatchewan); and Aiguo Dai (SUNY Albany).
Climate models and weather models have historically operated on different scales, both in time and space. Climate scientists are interested in large-scale changes that unfold over decades, and the models they've developed help them nail down long-term trends such as increasing surface temperatures, rising sea levels, and shrinking sea ice.
Climate models are typically low resolution, with grid points often separated by 100 kilometers (about 60 miles). The advantage to such coarse resolution is that these models can be run globally for decades or centuries into the future with the available supercomputing resources. The downside is that they lack detail to capture features that influence local atmospheric events, such as land surface topography, which drives mountain weather, or the small-scale circulation of warm air rising and cold air sinking that sparks a summertime thunderstorm.
Weather models, on the other hand, have higher resolution, take into account atmospheric microphysics, such as cloud formation, and can simulate weather fairly realistically. It's not practical to run them for long periods of time or globally, however — supercomputers are not yet up to the task.
As scientific understanding of climate change has deepened, the need has become more pressing to merge these disparate scales to gain better understanding of how global atmospheric warming will affect local weather patterns.
"The climate community and the weather community are really starting to come together," Rasmussen said. "At NCAR, we have both climate scientists and weather scientists, we have world-class models, and we have access to state-of-the-art supercomputing resources. This allowed us to create a data set that offers scientists a chance to start answering important questions about the influence of climate change on weather."
To create the data set, the research team used WRF to simulate weather across the contiguous United States between 2000 and 2013. They initiated the model using a separate "reanalysis" data set constructed from observations. When compared with radar images of actual weather during that time period, the results were excellent.
"We weren't sure how good a job the model would do, but the climatology of real storms and the simulated storms was very similar," Rasmussen said.
With confidence that WRF could accurately simulate today's weather, the scientists ran the model for a second 13-year period, using the same reanalysis data but with a few changes. Notably, the researchers increased the temperature of the background climate conditions by about 5 degrees Celsius (9 degrees Fahrenheit), the end-of-the-century temperature increase predicted by averaging 19 leading climate models under a business-as-usual greenhouse gas emissions scenario (2080–2100). They also increased the water vapor in the atmosphere by the corresponding amount, since physics dictates that a warmer atmosphere can hold more moisture.
The result is a data set that examines how weather events from the recent past — including named hurricanes and other distinctive weather events — would look in our expected future climate.
The data have already proven to be a rich resource for people interested in how individual types of weather will respond to climate change. Will the squall lines of intense thunderstorms that rake across the country's midsection get more intense, more frequent, and larger? (Yes, yes, and yes.) Will snowpack in the West get deeper, shallower, or disappear? (Depends on the location: The high-elevation Rockies are much less vulnerable to the warming climate than the coastal ranges.) Other scientists have already used the CONUS 1 data set to examine changes to rainfall-on-snow events, the speed of snowmelt, and more.
While the new data set offers a unique opportunity to delve into changes in weather, it also has limitations. Importantly, it does not reflect how the warming climate might shift large-scale weather patterns, like the typical track most storms take across the United States. Because the same reanalysis data set is used to kick off both the current and future climate simulations, the large-scale weather patterns remain the same in both scenarios.
To remedy this, the scientists are already working on a new simulation, nicknamed CONUS 2.
Instead of using the reanalysis data set — which was built from actual observations — to kick off the modeling run of the present-day climate, the scientists will use weather extracted from a simulation by the NCAR-based Community Earth System Model (CESM). For the future climate run, the scientists will again take the weather patterns from a CESM simulation — this time for the year 2100 — and feed the information into WRF.
The finished data set, which will cover two 20-year periods, will likely take another year of supercomputing time to complete, this time on the newer and more powerful Cheyenne system at the NCAR-Wyoming Supercomputing Center. When complete, CONUS 2 will help scientists understand how expected future storm track changes will affect local weather across the country.
Scientists are already eagerly awaiting the data from the new runs, which could start in early 2018. But even that data set will have limitations. One of the greatest may be that it will rely on a single run from CESM. Another NCAR-based project ran the model 40 times from 1920 to 2100 with only minor changes to the model's starting conditions, showing researchers how the natural chaos of the atmosphere can cause the climate to look quite different from simulation to simulation.
Still, a single run of CESM will let scientists make comparisons between CONUS 1 and CONUS 2, allowing them to pinpoint possible storm track changes in local weather. And CONUS 2 can also be compared to other efforts that downscale global simulations to study how regional areas will be affected by climate change, providing insight into the pros and cons of different research approaches.
"This is a new way to look at climate change that allows you to examine the phenomenology of weather and answer the question, 'What will today's weather look like in a future climate?'" Rasmussen said. "This is the kind of detailed, realistic information that water managers, city planners, farmers, and others can understand and helps them plan for the future."
High Resolution WRF Simulations of the Current and Future Climate of North America, DOI: 10.5065/D6V40SXP
Laura Snider, Senior Science Writer
Water managers and streamflow forecasters can now access bi-weekly, monthly, and seasonal precipitation and temperature forecasts that are broken down by individual watersheds, thanks to a research partnership between the National Center for Atmospheric Research (NCAR) and the University of Colorado Boulder (CU Boulder). The project is sponsored by the National Oceanic and Atmospheric Administration (NOAA) through the Modeling, Applications, Predictions, and Projections program.
Operational climate forecasts for subseasonal to seasonal time scales are currently provided by the NOAA Climate Prediction Center and other sources. The forecasts usually take the form of national contour maps (example) and gridded datasets at a relatively coarse geographic resolution. Some forecast products are broken down further, based on state boundaries or on climate divisions, which average two per state; others are summarized for major cities.
But river forecasters and water managers grapple with climate variability and trends in the particular watersheds within their service areas, which do not align directly with the boundaries of existing forecast areas. A forecast that directly describes predicted conditions inside an individual watershed would be extremely valuable to these users for making decisions in their management areas, such as how much water to release or store in critical reservoirs and when.
To bridge this gap, the NCAR–CU Boulder research team has developed a new prototype prediction system that maps climate forecasts to watershed boundaries over the contiguous United States in real time. The system is currently running at NCAR, with real-time forecasts and analyses available on a demonstration website.
"We are trying to improve the accessibility and relevance of climate predictions for streamflow forecasting groups and water managers," said NCAR scientist Andy Wood, who co-leads the project. "We can’t solve all the scientific challenges of climate prediction, but we can make it easier for a person thinking about climate and water in a river basin — such as the Gunnison, or the Yakima, or the Potomac — to find and download operational climate information that has been tailored to that basin’s observed variability."
The project is funded by NOAA, and the scientists plan to hand off successful components of the system for experimental operational evaluation within the NOAA National Weather Service. Collaborators include scientists from the NOAA Climate Prediction Center and partners from the major federal water agencies: the U.S. Army Corps of Engineers and the Bureau of Reclamation.
Precipitation and temperature forecasts that extend beyond the typical 7- to 10-day window can be useful to water managers making a number of important decisions about how to best regulate supplies. For instance, during a wet water year, when snowpack is high and reservoirs are more full than usual, the relative warmth or coolness of the coming spring can affect how quickly the snow melts. Good spring season forecasts allow water managers to plan in advance for how to best manage the resulting runoff.
For water systems in drought, such as California's during 2012–2015, early outlooks on whether the winter rainy season will help alleviate the drought or exacerbate it can help water utilities strategize ways of meeting the year’s water demands.
Historically, making these kinds of longer-term predictions accurately has been highly challenging. But in recent years, scientists have improved their skill at subseasonal and seasonal climate prediction. NOAA’s National Centers for Environmental Prediction plays a key role, both running an in-house modeling system — the Climate Forecast System, version 2 (CFSv2) — and leading an effort called the North American Multi-Model Ensemble (NMME). These model-based forecasts help inform the NOAA official climate forecasts, which also include other tools and expert judgment.
NMME combines forecasts from seven different climate models based in the U.S. and Canada to form a super-ensemble of climate predictions that extend up to 10 months into the future. The combination of the different forecasts is often more accurate than the forecast from any single model. Temperature forecasts, in particular, from the combined system are notably more accurate than they were 10 years ago, Wood said, partly due to their representation of observed warming trends. Even with these new tools, however, predicting seasonal precipitation beyond the first month continues to be a major challenge.
The NCAR–CU Boulder project makes use of both the CFSv2 and NMME forecasts. It generates predictions for bi-weekly periods (weeks 1-2, 2-3, and 3-4) from CFSv2 that are updated daily and longer-term forecasts derived from the NMME (months 1, 2, 3, and season 1) that are updated monthly. The scientists currently map these forecasts to 202 major watersheds in the contiguous U.S.
The resulting watershed-specific forecasts are available in real-time on the project's interactive website, which also provides information about their accuracy and reliability.
"It's important for users to be able to check on the quality of the forecasts," said Sarah Baker, a doctoral student in the Civil, Environmental, and Architectural Engineering Department at CU Boulder. "We're able to use hindcasts, which are long records of past forecasts, to analyze and describe the skill of the current forecasts.
Baker, who also works for the Bureau of Reclamation, has been building the prototype system under the supervision of Wood and her academic adviser, CU Professor Balaji Rajagopalan.
The researchers are also using analyses of forecast accuracy and reliability to begin correcting for systematic biases — such as consistently over-predicting springtime rains in one watershed or under-predicting summertime heat in another — in the forecasts.
The project team has presented the project at a number of water-oriented meetings in the western U.S. Water managers, operators, and researchers from agencies such as the Bureau of Reclamation and utilities such as the Southern Nevada Water Authority, which manages water for Las Vegas, have expressed interest in the new forecast products.
"This project has great potential to provide climate outlook information that is more relevant for hydrologists and the water sector. It will be critical to connect with stakeholders or possible users of the forecasts so that their needs can continue to help shape this type of information product," said NOAA’s Andrea Ray. Ray leads an effort funded by NIDIS, the National Integrated Drought Information System, to identify tools and information such as this for a NOAA online Water Resources Monitor and Outlook that would also help connect stakeholders to climate and water information.
In the coming year, the research team will implement statistical post-processing methods to improve the accuracy of the forecasts. They will also investigate the prediction of extreme climate events at the watershed scale.
CONTRACT
Andy Wood, NCAR Research Applications Laboratory
WEBSITEe
http://hydro.rap.ucar.edu/s2s
COLLABORATORS
CU Boulder
NCAR
NOAA
U.S. Army Corps of Engineers
Bureau of Reclamation
FUNDER
NOAA's Modeling, Applications, Predictions and Projections Climate Testbed program
The metrics featured below offer qualitative and quantitative measurements and assessments of the productivity, quality, and impacts that NCAR staff, programs and activities have on our research community, sponsors, and society in general for data reported in the Metrics Database, iVantage HRIS system and OpenSky Database as of October 31, 2018 for fiscal year 2018 (October 1, 2017 - September 30, 2018). Staff continue to update their entries and expand their contributions throughout the year so visit the Metrics Database for the most current data. (2018 METRICS AS OF OCTOBER 31, 2018). Date stamp 10/30/18.
In FY18, a total of 119 events were hosted: 43 workshops, 17 tutorials, five symposia, six conferences, and 48 colloquia with an average audience of 53 colleagues per event and estimated total audience of 6,315. Event co-sponsors groups included .
Each year, events are hosted by labs, divisions, and programs. These include colloquia, conferences, symposia, tutorials, and workshops.
Date Range | Total Hosted | Workshops | Tutorials | Symposia | Conferences | Colloquia |
FY18 | 119 | 43 | 17 | 5 | 6 | 48 |
NCAR’s geosciences research facilities, instrumentation and field support services support field campaigns around the globe.
Date Range | Total Campaigns | Institutions | PIs | Undergraduate Students | Graduate Students |
FY18 | 7 | 40 | 42 | 34 | 72 |
In FY18, NCAR participated in seven field campaigns ranging in duration from 60 to 1,318 operational field days. A total of 40 institutions, including 26 UCAR member institutions participated in these campaigns. The projects involved 42 investigators, 34 undergraduate students, and 72 graduate students.
Campaign Acronym | Campaign Full Name |
SOCRATES | Southern Ocean Clouds, Radiation, Aerosol Transport Experimental Study |
SAVANT | Stable Atmospheric Variabilitiy and Transport |
WE-CAN Test Flights | Western Wildfire Experiment for Cloud Chemistry, Aerosol, Absorption and Nitrogen |
GRAINEX | The Great Plains Irrigation Experiment |
RELAMPAGO | Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations |
HiWIND Relaunch | HiWIND Relaunch |
IDEAL | Instabilities, Dynamics and Energetics accompanying Atmospheric Layering |
One example is the Stable Atmospheric Variabilitiy and Transport (SAVANT) project, an NSF sponsored field campaign focused on quantifying, through a field measurement campaign, the effects of converging shallow cold air drainage and background flow on aerosols transport and dispersion. The novel aspect of this work was the ability to identify turbulent events and features with aerosol lidars to add the missing spatial component to our current understanding.
NCAR-Wyoming Supercomputer
Each year, NCAR facilities host tours organized for a specific organization or group. This year, NCAR hosted a total of 96 tours, between the four locations.
The NCAR-Wyoming Supercomputer Center (NWSC) is based in Cheyenne, Wyoming. The Center provides advanced computing services to scientists studying a broad range of disciplines, including weather, climate, oceanography, air pollution, space weather, computational science, energy production, and carbon sequestration. The Center is open to the public for self-guided tours, field trips for school groups, and non-school group special tours. In FY18, the Center received 1840 walk-in public visitors, and averaged 153 visitors per month.
Date Range | Hosted Tours | K-12 Groups | Science/Technical Tours | College/University Groups | Political/Sponsor Groups | Peer Center |
FY18 | 53 | 8 | 10 | 16 | 7 | 12 |
NWSC hosted 53 tours in FY18, for groups ranging in size from 1 to 88 people. Eight tours were for K-12 groups, including Gilchrist Elementary School (Colorado) and various local school visits. Ten groups took science- or technical-related tours, including a group from the IBS Center for Climate Physics, South Korea. There were 16 college or university groups, ranging from Casper College (Colorado) to Mississippi State University. There were seven tours by political/sponsor groups, including the Department of Homeland Security and the National Science Foundation/House Appropriations Committee. Additionally, twelve peer centers visited, ranging from Greenhouse Data to HPE Samsung.
NCAR Research Aviation Facility at the Rocky Mountain Metropolitan Airport
Date Range | Total Hosted Tours | K-12 Groups | Science/Technical Tours | College/University Groups | Political/Sponsor Groups |
FY18 | 36 | 5 | 12 | 10 | 9 |
The Rocky Mountain Metropolitan Airport hosted a total of 36 tours in FY 2018. Ten tours were for college and university groups, including WE-CAN campaign team and a Colorado University Global Carbon Cycle Class. Nine tours were for political and sponsor groups, including Senator Cory Gardner’s office and Admiral Nancy Hann. There were also five tours provided to K-12 groups, including one from the Saint Vrain Valley School District (Colorado). This year there were twelve science/technical tours provided to groups ranging from the Meteo-France office to Harvard Medical School’s Department of Biological and Medical Systems.
The High Altitude Observatory
Date Range | Total Hosted Tours | K-12 Groups | Science/Technical Tours | College/University Group | Political/Sponsor Groups |
FY18 | 7 | 1 | 4 | 1 | 1 |
The High Altitude Observatory hosted a total of 7 tours in FY18. One tour was for the University of Hawai’i. There was one tour for the Ouray High School from the K-12 group. There were also four science and technical tours provided to NIST and LASP Scientists.
NCAR staff members serve as research advisors and thesis committee members for graduate students around the world.
Date Range | Total Students | International Service | U.S. Service |
FY18 | 210 | 27% | 73% |
In FY 2018, NCAR staff served as graduate advisors or committee members for 210 graduate students. Twenty-one of those are working on their M.S. degree and 189 are working on their Ph.D. Seventy-three percent of students attend U.S. universities, whereas 27% study at schools in 16 different countries world-wide including a PhD student from the National Cheng Kung University who was advised by Nicholas Pedatella, a PhD student from the University of Sheffield advised by Louisa Emmons, and a Master’s student from the University of Alabama, Huntsville advised by Tammy Weckwerth.
NCAR staff members serve as publication editors. These positions recognize the appointee's leadership in the field and serve a critical role in developing a given field's future focus.
Date Range | Total Editorships | Different Publications/Journals |
FY18 | 92 | 107 |
92 NCAR staff served in editorial roles for 107 different publications or journals. Hugh Morrison served the Editor for the Monthly Weather Review while Danica Lombardozzi served as a Review Editor for the Frontiers in Forest and Global Change. Publications included top-tier journals such as the Monthly Weather Review and the Journal of Climate.
Every year a significant number of NCAR Staff are honored for their scientific excellence and community contributions to the Atmospheric and related sciences.
Date Range | Total External Awards |
FY18 | 36 |
Gordon Bonan (CGD) was named American Meteorology Society Fellow. The AMS Fellow honor celebrates outstanding contributions to the atmospheric or related oceanic or hydrologic sciences or their applications during a substantial period of years.
Four scientists received awards from the American Geophysical Union (AGU) to include Linda Mearns, selected speaker for the 2017 Stephen H. Schneider Memorial Lecture, Mary Hudson received the John Adam Fleming Medal, Clara Deser received the Bjerknew Lecture and Kevin Trenberth was awarded the 2017 Roger Revelle Medal.
A fellowship is typically a special appointment granting support for a term in order to support advanced research or study.
Date Range | Total Fellowships |
FY18 | 6 |
Eight UCAR staff received fellowships in 2018. Among the highlights: Sophie Hou (CISL) was awarded the Earth Science Information Partners Fellowship offered by the Foundation for Earth Science and James Done (MMM) was awarded the Willis Research Fellow Postdoctoral Fellowship from the Willis Research Network.
Staff across NCAR work directly with classes and groups of K-12 students to develop or deliver lectures, conduct tours, and lead or participate in field trips and other educational activities.
Date Range | Total K-12 Outreach | Schools/Events | Communities Reached |
FY18 | 45 | 58 | 19 |
Forty-five NCAR Staff worked with K-12 students from 58 schools or other school based organizations. Activities included judging at the Colorado Science and Engineering Fair, helping teachers, mentoring, and field trips reaching 19 different communities. Examples range from volunteering at the Louisville Elementary School in Louisville, Colorado to being a learning fair judge at Ryan Elementary School in Lafayette, Colorado.
Among the highlights: Bill Mahoney (RAL) supports the Snow Plow Painting Art Project involving more than 200 kids, on an annual basis (since 2003). This project brings awareness of the City of Louisville’s winter snow and ice control operations and the safety hazards associated with winter conditions by bringing together school students, city operations officials, and weather experts. Art classes at each of the participating schools design artwork consistent with the designated theme for the year and the artwork is then painted on the snow plows. Seven schools in Louisville participate in this project; Mark Miesch (HAO) was on the Board of Directors at the National Space Science and Technology Institute/Pikes Peak Observatory in Colorado Springs which serves approximately 300 students; and John Sobtzak conducted an elementary school presentation on the Colorado Earth Escape Explorer (CU-E3) cubesat as part of CU's Aerospace Engineering department's Graduate Projects class at Hill City School in Hill City, Minnesota and and Northern Lights Community School in Warba, Minnesota.
NCAR staff participate in mentoring colleagues and students.
Date Range | Total Mentoring |
FY18 | 117 |
During this year, 117 staff members mentored mentees both inside and outside of NCAR. Rebecca Buchholz (ACOM) was a mentor to students from the Colorado School of Mines, University of Oklahoma and the University of Colorado. Wojciech Grabowski (MMM) was a science mentor for a PhD student from the Indian Institute of Tropical Meteorology, Pune, India.; Julie Harris (CISL) was a co-mentor of the ISGB for the CISL Student Assistant ship program during 2017-2018 school year while Gang Lu (HAO) worked with a student from Clemson University over the summer to teach him to process and analyze various data sets and to use the AMIE codes.
NCAR Staff give presentations about data, models, theories, hypotheses, reviews, and results around the world in talks and posters to audiences ranging from scientists and engineers to the general public.
Date Range | Audience Totals | NCAR Staff - Talk/Poster Presentations |
FY18 | 1000+ | 1100+ |
Many thousands of people were in the audience when 212 NCAR staff presented over 900 talks globally, from Argonne, Illinois to Paris, France. Examples range from Susan Bates' (CGD)) talk on “Blue Waters Enabled Advances in the Fields of Atmospheric Science, Climate, and Weather?” at the Blue Waters Users Symposium in Sunriver, Oregon, to Sean Burns’ (MMM) talk “Using Measured Latent Heat Flux from a Colorado Subalpine Forest to Assess Modeled CLM4.5 Latent Heat Flux” at the 33rd Conference on Agricultural and Forest Meteorology in Boise, Idaho.
Ninety-six NCAR staff made more than 140 poster presentations globally, from Santa Fe, New Mexico to Ede, Netherlands. Examples include Cathy Kissinger’s (RAL) poster "An Update on the Global Weather Hazards Project and Next Steps” in Austin Texas at the Sixth Aviation, Range, and Aerospace Meterology Special Symposium and Hugh Morrison’s (MMM) poster “Theoretical expressions for the ascent rate of moist deep convective thermals” in Lorne, Australia at the 2nd GASS Conference.
Date Range | Total Teaching Appointments | Countries | U.S. States |
FY18 | 41 | 12% | 88% |
NCAR staff members make important contributions through teaching appointments at institutions of higher education in different positions ranging from Graduate Faculty to Professor.
Teaching appointments at institutions of higher education currently number 41. Twelve percent of these appointments occur in 5 international countries; 88% took place in 11 U.S. states. The longest term is 33 years, by Grant Branstator (CGD) who is an Adjunct Professor at Iowa State University. The class sizes range from 4 to 80 students.
NCAR staff teach classes and offer training in workshops, tutorials, and colloquia to colleagues and students ranging from model users, to scholars, to fellow researchers.
Date Range | UCAR Staff Members | Workshops/ Tutorials/ Colloquia | # of Classes | # of Participants | Countries | U.S. States |
FY18 | 79 | 134 | 493 | 5900+ | 10 | 9 |
During this year, 79 staff members taught at a total of 134 workshops, tutorials, and colloquia. In all, 493 individual classes were taught, with class sizes ranging from three to 1,000 people. Sixteen percent of these events occurred in the following 10 international countries: Australia, Brazil, China, Germany, Italy, Netherlands, Norway, South Korea Sweden and the U.K.; 85% took place in nine U.S. states, including Idaho and Florida. Examples range from Jeff Anderson's (CISL) appointment as Lecturer to the Model Coupling and Data Driven Simulations of Solar Eruptions course in Boulder, Colorado to Bill Lipscomb (CGD) instructing at a CESM Tutorial session in Boulder, CO.
NCAR staff are called upon to participate in and often lead external scientific, technical, policy, and educational committees. These committees are instrumental to advancing and promoting the work of the scientific and technical community.
Date Range | Total External Committees | NCAR Staff Served | Service on more than one committee |
FY18 | 535 | 181 | 60% |
This year, 181 NCAR staff served in a multitude of roles on 535 external committees (an average of 3.0 committees per participating staff member) for national and international scientific, education, and governmental organizations, including entities such as the American Geophysical Union, the National Academy of Sciences and the Study of Environmental Arctic Change. More than 60% served on more than one committee.
NCAR staff take leaves to visit other institutions for two weeks or more for intellectual growth, professional development, collaboration with research community peers, community support, teaching, or sabbatical. Examples of work include teaching courses or workshops, lecturing, giving tutorials, working with graduate students on dissertation-focused research, student mentoring, collaborative research, and participating in the host institution's outreach to community colleges, minority-serving institutions, and high schools.
Date Range | NCAR Staff Members | Institutions |
FY18 | 5 | 5 |
This year, 5 NCAR staff members took leaves at 5 different institutions, ranging from the University of Hawai’i to the University of Leeds. Among the highlights: Frank Bryan (CGD) participated in a program on Planetary Boundary Layers at Kavli Institute for Theoretical Physics at the University of California, Santa Barbara and Naoki Mizukami (RAL) visited the Helmholtz Centre for Environmental Research to work on the development of hydrologic model parameter estimation tools, and research papers in Leipsig, Germany
NCAR Affiliate Scientists
Select university and research-community scientists are invited to carry out long-term, highly interactive, collaborative work with UCAR scientists and are appointed as Affiliate Scientists with three-year terms (see list). This appointment is particularly suitable for parties who desire an extended, close-working relationship on scientific problems of mutual interest. Currently, 46 scientists hold appointments including Dr. Kevin Repasky of Montana State University. Dr. Repasky is collaborating with scientists in the Earth Observing Laboratory(EOL) on developing a deployable version of a low-cost water vapor differential absorption lidar (WV DIAL).
NCAR Affiliate Scientist | Home Institution |
Dr. Elliot Atlas | University of Miami |
Dr. Bernard Aumont | Laboratoire Interuniversitaire des Systemes Atmospherieques (LISA) |
Dr. Dale Barker | United Kingdom Meteorological Office |
Dr. Alan Blyth | University of Leeds |
Prof. Lance Bosart | State University of New York Albany |
Dr. James Brasseur | University of Colorado |
Dr. Natalia Calvo | Universidad Complutense de Madrid |
Dr. Guido Cervone | Pennsylvania State University |
Dr. Paul Charbonneau | University of Montreal |
Dr. Shuyi Chen | University of Miami |
Prof. Philip Chilson | University of Oklahoma |
Prof. Cathy Clerbaux | CNRS |
Dr. Enrique Curchitser | Rutgers University |
Dr. Ineke de Moortel | University of St. Andrews |
Dr. Leo J. Donner | NOAA GFDL |
James Doyle | U.S. Naval Research Laboratory |
Dr. Veronika Eyring | German Aerospace Center |
Dr. Jerome Fast | Pacific Northwest National Laboratory |
Dr. Michael Ferrari | aWhere |
Dr. Paul Field | Met Office |
Dr. Silvano Fineschi | Osservatorio Astrofisico di Torino |
Dr. John Finnigan | CSIRO, Australia |
Dr. Mary Hayden | University of Colorado |
Dr. Song-You Hong | Yonsei University |
Dr. Joseph Huba | Naval Research Laboratory |
Dr. Mary Hudson | Dartmouth College |
Dr. Harm Jonker | Delft University of Technology |
Dr. Reto Knutti | ETH Zurich, Switzerland |
Dr. Hao-Sheng Lin | University of Hawai'i Manoa |
Dr. Elisabeth Lloyd | Indiana University |
Dr. William Lotko | Dartmouth College |
Dr. Latty Mahrt | Oregon State University |
Jakob Mann | Technical University of Denmark |
Dr. Marty Mlynczak | NASA Langley Research Center |
Dr. Antonio Navarro | Instituto Nazionale di Geofisica e Vulcanologia |
Dr. Phiippe Naveau | Laboratoire des Sciences du Climat et I'Environnement (LSCE) CNRS |
Dr. Bart Nijssen | University of Washington |
Prof. Lorenzo Polvani | Columbia University |
Dr. Mark Rast | University of Colorado |
Dr. Kevin Repasky | Montana State University |
Dr. Alfonso Saiz-Lopez | Ministerio de Ciencia e Innovaction, Madrid |
Prof. Gunilla Svennson | University of Stockholm |
Dr. Laurent Terray | CERFACS |
Prof. Javier Trujillo-Bueno | Instituto de Astrofisica de Canarias |
Dr. Lian-Ping Wang | University of Deleware |
Prof. Mei Zhang | Chinese Academy of Sciences |
Emeritus/Emerita
Scientific and Research Engineering staff who have made significant contributions to NCAR through long and distinguished service in senior positions in research may be granted emeritus or emerita status (see list). This designation confers a life-long honorary distinction. Approval of the President and the Board of Trustees is required. Currently the ranks of Emeritus/Emerita number 28 with the recent appointment of Mr. Richard “Rit” Carbone who is continuing his research on root causes of tropical oceanic rainfall errors in highly parameterized global models.*deceased
Emeritus/Emerita | Year of Appointment |
Jack Calvert | 2002 |
Rit Carbone | 2016 |
Al Cooper | 2013 |
James Dye | 2003 |
Fred Eisele | 2009 |
John Firor* | 1999 |
Brant Foote | 2017 |
John Gille | 2015 |
Peter Gilman | 2009 |
Roy Jenne* | 2013 |
Maura Hagan | 2015 |
Jackson Herring | 1998 |
Richard Katz | 2013 |
Charles Knight | 2013 |
Joachim Kuettner* | 2007 |
Margaret Lemone | 2009 |
Donald Lenschow | 2011 |
Bruce Lites | 2013 |
Roland Madden | 2002 |
William Mankin | 2003 |
Annick Pouquet | 2013 |
Art Richmond | 2017 |
Brian Ridley | 2007 |
Raymond Roble | 2009 |
Bob Serafin | 2001 |
Paul Swartztrauber* | 2004 |
David Williamson | 2014 |
Jim Wilson | 2014 |
*deceased
Date Range | Total Scientific/Technical Visits | 1-7 days | 8-14 days | 2 weeks-2 months | 2-6 months | 6 months or longer |
FY18 | 780 | 167 | 77 | 210 | 169 | 157 |
Each year students, scientists, engineers, weather forecasters, and other professionals from around the country and world receive special visitor appointments from labs and programs across NCAR to collaborate with scientific, educational, or technical staff; conduct independent research; or participate in and/or oversee a professional project. Many receive financial support for their visits and some visitors temporarily join the NCAR staff.
This year, colleagues visited NCAR 780 times and hailed from 336 institutions, located in 44 different U.S. states and 38 different countries.