Oceanic Weather

BACKGROUND

Weather conditions can seriously restrict aircraft operations and levels of service available to system users.  Thus, the manner by which weather is observed, forecasted, disseminated, and used in decision-making is of critical importance.  Aviation users operating within oceanic and remote regions have limited access to high-resolution (temporal and spatial) weather products that depict the current and future locations of deep convection and turbulence.

To address these needs, RAL scientists are developing weather products to identify and characterize the oceanic/remote occurrence of deep convection.  Global ensemble forecasts are being utilized to provide probabilistic guidance of convective storm hazards for strategic (24-36 hr) flight planning purposes as needed for transoceanic flights.  The near-global convection diagnosis system detects deep convection using satellite-based methodologies, global lightning data and numerical model results. Two products in the system, the Cloud Top Height (CTH) and the Convective Diagnosis Oceanic (CDO), are being displayed on the flight decks of Lufthansa Airlines and Brussels Airlines aircraft, as part of the Global Weather Hazards project. By the end of 2017, the FAA Weather Technology in the Cockpit (WTIC) will be displaying the CTH and CDO products within the cockpit of three domestic airlines as part of the Remote Oceanic Meteorology Information Operational (ROMIO) demonstration. Accomplishments and plans related to the ongoing research and development of convection weather products are discussed below.

ENSEMBLE PREDICTION OF OCEANIC CONVECTIVE HAZARDS (EPOCH)

Use of ensemble probabilistic forecasts is one way of addressing uncertainty in convective hazard forecasting.  RAL has been developing such a forecast product (EPOCH) to provide probabilistic guidance on convective storm hazards for transoceanic flights at lead times of 24 – 36 hours.  RAL’s approach of fusing ensemble forecasts provided by several global prediction centers is being utilized to facilitate global harmonization of World Area Forecast System (WAFS) products. 

FY2017 Accomplishments

Figure 1. Display of Cloud Top Height (CTH; left) and Convective Diagnosis Oceanic (CDO; right) products. Both products are overlaid with ASDI flight tracks shown with the orange/yellow lines and a red arrowhead that indicates flight direction. Aircraft current position is shown with the red box with 15 min flight legs before and ahead of the aircraft. Turbulence pilot reports are also indicated (Ʌ). The region shown is north of Haiti and the Dominican Republic
Figure 1. Display of Cloud Top Height (CTH; left) and Convective Diagnosis Oceanic (CDO; right) products. Both products are overlaid with ASDI flight tracks shown with the orange/yellow lines and a red arrowhead that indicates flight direction. Aircraft current position is shown with the red box with 15 min flight legs before and ahead of the aircraft. Turbulence pilot reports are also indicated (Ʌ). The region shown is north of Haiti and the Dominican Republic

This past year efforts were focused on refining the methodology of fusing data from multiple global numerical prediction centers and bias-correcting the probabilistic guidance product.  Significant progress was made with the development and testing of an adaptive-scale, dynamic bias correction process to allow automated adjustments for model errors.  The current real-time prototype was updated to include this new capability, using global ensemble forecasts from the United States and Canada’s numerical prediction centers. Ensemble data from other international prediction centers continue to be explored in an off-line mode.

Efforts continue to refine proxy-truth fields based on satellite and global lightning data to enable assessment and calibration of the probabilistic convective storm hazard guidance products.  The two truth fields used thus far are the CTH and the CDO products, discussed more fully in the following section. An effort is underway to analyze flight position data from the Aircraft Situation Display to Industry (ASDI) to better quantify thresholds that define convective hazards (Figure 1). The truth field development is largely based on efforts previously funded by FAA and NASA efforts for the detection and nowcasting of oceanic convection and can be viewed at http://www.rap.ucar.edu/projects/ocn/realtime_sys.

This effort is conducted in close collaboration with the NWS Aviation Weather Center (AWC), which currently receives products from RAL’s prototype system and provides feedback based on experimental evaluations (e.g., within the Aviation Weather Testbed).

FY2018 Plans

During the coming year, the prototype capability will be further enhanced based on performance assessment and feedback received from AWC forecasters.  In addition, the cloud top product will undergo further fine-tuning and calibration.  Experimental approaches to produce more reliable and sharper probability fields will be examined.  A technology transfer effort of the software will be initiated, with an aim to install the processes at NCEP to support the WAFS.  Collaboration with AWC will continue along with efforts investigating performance from combined probabilistic forecasts using additional input from the UK Met Office ensemble.

GLOBAL WEATHER HAZARDS

Figure 2. Lufthansa Airlines eRM display of the CDO and CTH polygons. Color shapes represent the CDO interest values as follows: green is >2 and yellow is >3. The grey shapes are CTH contours beginning at >30 kft (FL300) with darker shapes indicating higher contours at increments of 5 kft to a maximum of >50kft (FL500). The area shown includes Inter-Tropical Convergence Zone (ITCZ) over the northern part of South America. Storm motion vectors are shown with red arrows. NWS Convective SIGMETs are shown with the tan polygons.
Figure 2. Lufthansa Airlines eRM display of the CDO and CTH polygons. Color shapes represent the CDO interest values as follows: green is >2 and yellow is >3. The grey shapes are CTH contours beginning at >30 kft (FL300) with darker shapes indicating higher contours at increments of 5 kft to a maximum of >50kft (FL500). The area shown includes Inter-Tropical Convergence Zone (ITCZ) over the northern part of South America. Storm motion vectors are shown with red arrows. NWS Convective SIGMETs are shown with the tan polygons.

Inflight display of products depicting convective hazards are needed by pilots of transoceanic aircraft to assist with strategic route planning during long flights (up to ~17 hr). Such displays will enable pilots to see potential convective hazards along the entire flight route, beyond the range of the onboard radar and reference the products while planning for future avoidance maneuvers. These new products are supplemental to the onboard weather radar for operational or tactical decisions.  Using satellite-based algorithms augmented with global lightning data and global numerical model results, two convective products, the CTH and the CDO, are providing real-time, operational guidance to Lufthansa Airlines and Brussels Airlines pilots. The products are uplinked into the flight deck and subsequently displayed on an Electronic Flight Bag (EFB) developed by Lufthansa Integrated Dispatch Operation (LIDO) named the eRouteManual (eRM). An application, called WxClient, displays the selected CTH and CDO products on the eRM.

After a successful feasibility study was completed in 2014 to examine the usefulness of the CTH product displayed on the LIDO eRM, the Global Weather Hazard (GWH) project began in 2015 with a partnership between Lufthansa Airlines, Basic Commerce & Industries, Inc. (BCI), NCAR and the Weather Solutions Division of the Sutron Corporation. This project is a 2-yr commercial effort that has expanded coverage to a global domain with latitude limits of -50S to 70N. Display of both the CTH and the CDO products are shown on the LIDO eRM’s of Lufthansa Airlines B747-8 aircraft and the Brussels Airlines fleet (Figure 2). About 50 aircraft currently receive the two products. The CTH and CDO polygons are displayed over the navigational charts on the eRM and provide the pilot with situational awareness of convective hazards over the planned flight route.

FY2017 Accomplishments

The CTH/CDO oceanic convection diagnosis system was successfully run during the fiscal year, providing convective hazard guidance to Lufthansa Airlines and Brussels Airlines pilots. The products are commercially available through BCI.

 FY2018 Plans A follow on contract with BCI is underway.

WTIC Remote Oceanic Meteorology Information Operational (ROMIO) Demonstration

The FAA WTIC ROMIO demonstration is analyzing oceanic aviation inefficiencies in current or future NextGen operations caused by gaps in either the available meteorological information or in the technology utilized in the cockpit.  Using an operational demonstration to uplink convective weather products into the cockpit of domestic airlines, this effort helps to identify and analyze operational gaps.

Figure 3. The BCI Viewer showing the CTH and CDO products for ROMIO.
Figure 3. The BCI Viewer showing the CTH and CDO products for ROMIO.

In late FY2016 through FY2017, the WTIC ROMIO team began the execution of the Operational Plan written during an earlier effort in FY2015. The ROMIO Operational Plan considers all aspects of the demonstration from the availability and ingest of meteorological data sets, to the creation of weather products and to their dissemination to the aircraft. Other considerations include the training of the flight crews on the capabilities and limitations of the products, understanding how pilot decision-making might be facilitated with the convective products and soliciting flight crew feedback. The ROMIO demonstration is planned for three phases. Phase 1 is completed and the Operational Plan is approved. Phase 2 will plan for and then commence the operational demonstration. Phase 3 will include a validation effort to examine feedback from pilots, Airline Operations Centers and FAA Oceanic Control Centers to determine how the products filled existing gaps in meteorological information or in the technology utilized in the cockpit. Three domestic airlines are participating: Delta Air Lines, United Airlines and American Airlines. Other partners include NCAR, BCI, Panasonic, Gogo and Virginia Polytechnic Institute and State University as well as various FAA groups.

See Dissemination of Aviation Weather Information for more information on the FAA WTIC program.

FY2017 Accomplishments

Planning for the operational demonstration nears completion with planning documents having been written and approved.  Three FAA Oceanic Control Centers (Oakland, Houston and Miami) were briefed and agreed to participate in the ROMIO demonstration. The FAA Safety Risk Management Panel met in May 2017 and approved the demonstration plans. The airlines have written scenarios for their expected routes and aircraft that will use the two products. The NCAR Satellite Processing Plan describes the operational system that creates the CTH and CDO products in real-time over a domain that includes the GOES-East and GOES-West satellites coverage area. The ROMIO BCI Viewer was developed to display the CTH/CDO products and flight route information on tablets in the cockpit or on the web. Pilot training material was provided to the airlines. The Communications Plan, written by NCAR, describes communications between the ground and the aircraft, with final testing to be accomplished in December 2017. The Benefits Analysis, led by Virginia Polytechnic Institute and State University, was begun in late FY2017.

FY2018 Plans

During FY2018, the ROMIO operational demonstration will be conducted and will include selected flights from United Airlines, Delta Air Lines and American Airlines. Feedback from pilots, the Airlines Operations Centers, and the FAA Oceanic Control Centers will be collected and analyzed to ensure that project goals are met. The demonstration will begin in December 2017 and continue for 9-12 months. The Virginia Polytechnic Institute and State University will conduct a benefits analysis of the project.