Goal Area: Weather Technologies for the Global Air Transportation System
Motivation
RAL has spent the past twenty-eight years addressing and supplying the needs of aviation stakeholders in the U.S. and other countries. This work has yielded fundamental improvements in the scientific understanding of aviation weather hazards as well as a broad array of practical tools and systems that reduce the vulnerability of aviation to such hazards.
Current and projected growth in the volume, complexity, and economic importance of air and space transportation clearly demonstrates the need for a new paradigm supporting the organization and control of air traffic services in the 21st century. Since weather conditions seriously impact air traffic operations and the levels of service available to system users, the manner by which weather is observed, forecast, disseminated and used within air traffic decision processes and systems is of critical national importance.
Many new factors compound the challenge to safe and efficient air and space operations during the first twenty five years of this century. Among these factors are the following:
- Passenger and freight load requirements will be 2-3 times higher.
- No new airports are planned during the next decade.
- Airport expansion is limited at some major airports.
- New aircraft types such as very light jets and unmanned aerial vehicles (UAVs) are proliferating.
- Commercial space vehicles will begin operations by 2009.
- Increasing use of polar routes will introduce new hazards to crews and passengers.
- New navigational technologies that allow more flexible routing and separation of aircraft are not fully compatible with the current air traffic control system.
Capacity will become an increasingly limiting factor at many airports. Efficiency of flight operations en-route will become more critical. Predicting traffic loading accurately at all locations within the airspace system several hours in advance will be critical to efficient operations. Space operations with commercial passengers will require many safeguards for launch, sub-orbital flight, orbital flight and recovery.
The Next Generation Air Transportation System (NextGen) is now beginning to take shape on the design board of several federal agencies under the auspices of the Joint Program Development Office (JPDO). The JPDO has parsed the complex next generation system into several components and has endorsed the concept of Interagency Working Groups to manage the R&D associated with each. One such Working Group is dedicated to developing the weather information needs of NextGen and providing common weather-related decision information to all stakeholders within the system.
Near-Term Objectives
Advanced Weather Products for the Next Generation Air Transportation System (2009-2013)
The NextGen System is a national priority to meet the air transportation needs of the U.S. in the 21st century – in particular, a significant growth in demand for air traffic services, possibly on the order of three times today's demand levels. Since weather conditions can seriously restrict aircraft operations and levels of service available to system users, the manner by which weather is observed, forecast, disseminated, and used in decision–making is of critical importance.
Convective Weather (2009-2013)
The current convective weather focus is on the development of a Consolidated Storm Prediction for Aviation (CoSPA) forecast product, based upon feature extraction and extrapolation techniques, numerical weather prediction models, and intelligent blending of multiple forecast fields. The ability to skillfully predict storm organization and structure, and the evolution of storms throughout their life cycle, will be particularly relevant. Moreover, through the use of RAL's thunderstorm Auto-Nowcaster, we are learning how a human forecaster can add value to an automated weather prediction process in order to enhance the forecast quality. The lessons learned from this work will be incorporated into CoSPA. The research and development efforts have to include model development, especially improved initialization and data assimilation procedures. Furthermore, information from new sources, such as advanced radar technology and satellite observations, will have to be harvested for CoSPA. For oceanic convective forecasts in data-sparse areas it will be essential to combine satellite-based products with global-scale models.
Actions:
2009-2011 – Work collaboratively with the Massachusetts Institute of Technology (MIT) Lincoln Laboratory and the National Oceanic and Atmospheric Administration (NOAA) to build and test Version 1 of CoSPA that will serve as the single authoritative source to NextGen for summer and winter storms. This will require significant research that is directed to numerical model development and improved convective parameterization. It is to also include integration of convective weather data with air traffic management data to quantify the effects of convective weather on airspace capacity, defining and evaluating uncertainty, coupling intelligent forecast algorithms with automated traffic flow models and evaluating air traffic management requirements for forecast specificity at forecast periods out to 36 hours.
Icing (2009 – 2013)
RAL will continue to improve automated in–flight icing diagnosis and forecast algorithms by upgrading them as operational models are upgraded (such as the Weather and Research Forecasting model, WRF), by investigating and incorporating new data sets (including NASA Langley's advanced satellite products), and by learning how to use existing data sets more intelligently (such as NEXRAD radar data). Collaborations with aircraft manufacturers and aerospace engineers will result in improved descriptions and depictions of icing severity. A new project is the development of a warning tool for regions of high ice crystal content, which have been responsible for jet engine power rollbacks and, in some cases, total power loss during flight. Better parameterization of cloud processes in numerical weather models for 0–12 h forecasts will focus on weakly–forced cloud systems, the impact of cloud–active aerosols and parameterizations of size distributions for water drops and ice crystals. Global applications using combinations of global weather models and satellite information will be developed to support oceanic flight routes, as well as to provide guidance for re–entry of space vehicles. RAL will also seek opportunities to work with NASA and industry on improved terminal–area in–flight icing detection systems (such as the NASA Icing Remote Sensing System) incorporating previous research results into operational facilities.
Actions:
2009–2012 – Extend the capabilities of the current and forecast icing algorithms by:
Winter Weather (2009 – 2013)
The Weather Support for Deicing Decision Making (WSDDM) system combines a radar feature extraction and extrapolation algorithm with high–resolution surface liquid–equivalent precipitation measurements to estimate how much water substance will fall on aircraft between a de–icing event and takeoff. Future research activities will be focused on understanding how snowbands are organized, how their movement and behavior can be accurately predicted (especially on a 0–6 h timeframe), and real–time identification of precipitation type. Research will also be conducted on development of improved deicing fluid test systems, and on snow gauge evaluations. Combining the small–scale WSDDM detection and prediction capability with the larger–scale CoSPA effort will produce better situational awareness for both winter and summer storms.
Actions:
Refocus the ground deicing decision system on research to better forecast specific snow bands in terms of movement, precipitation type and evolution. Migrate these new capabilities into CoSPA in the 2011–2012 time frame.
Turbulence (2009 – 2013)
The prediction of turbulence using operational numerical weather prediction models will continue to challenge RAL scientists. The Graphical Turbulence Guidance (GTG) has operational and experimental versions that predict clear–air turbulence related to upper–level fronts and jet streams and mountain waves out to 12 h. Future versions will include terrain–induced turbulence and turbulence associated with convection, thus expanding the altitude range covered as well as the utility of the product. Research will also be conducted on improved turbulence parameterizations, better use of increased model resolution, increased understanding of all turbulence generation and downscaling mechanisms, and incorporation of new observational data. This will be done through high–resolution model simulations and by pursuing opportunities for collecting research quality in situ aircraft data.
The turbulence detection network based on NEXRAD radars will be expanded and incorporated into the GTG automated forecasting system. A global turbulence product is under development that combines model output results with satellite imagery to detect and predict turbulence from clear air and convective sources. In situ turbulence measurements (from commercial airlines and TAMDAR sensors) will supplement pilot reports (PIREPs) and airborne radar forward–looking turbulence detection algorithms (in cloud). Diagnostic and prognostic techniques for turbulence and wind shear above the tropopause will be developed to support aviation and space launch operations. Finally, RAL will complete the deployment of the Juneau turbulence warning system and subsequent handover to the FAA.
Actions:
2009–2012 – Extend the capabilities of the Graphical Turbulence Guidance by:
Ceiling and Visibility (2009 – 2013)
Work is nearly complete on a first–generation continental U.S. (CONUS) diagnosis product that represents carefully interpolated ceiling and visibility conditions between observing points. A second–generation product will implement more rigorous probabilistic representation of these conditions.
The goal is probabilistic ceiling and visibility forecasts with outlook horizons of up to 30 h. RAL's approach is to maximize the use and synthesis of existing operational models, model output statistics (MOS)–based guidance and other forecast products such as CoSPA. These resources will be augmented with an observation–based forecast component to boost forecast performance from 1 to 6 h. In mature form, the system will forecast the probabilities for ceiling and visibility conditions ranging from fully obscured to clear. The goal for short–range forecasts is an update rate of 5–15 min, while longer-range forecasts will be updated hourly, over both CONUS and Alaska domains.
Actions:
2009–2013 – Extend current national ceiling and visibility product capability through work to:
NextGen Network Enabled Weather (NNEW) (2009 – 2013)
trajectory within the gridded "data cube"
RAL is heavily engaged with the FAA, NOAA, Department of Defense (DoD), and MIT/Lincoln Labs in the development of a capability called NextGen Network Enabled Weather (NNEW). This capability will provide a global four–dimensional database of all weather information relevant to aviation decision–making. This so–called "4D data Cube" will be a distributed entity that exists through the application of modern information technology to store and retrieve data. To facilitate this effort, RAL is involved with the Open Geospatial Consortium and with DoD's steering activity for its Joint Meteorological and Oceanographic (METOC) Broker Language (JMBL), and various other standards bodies, to motivate the development of open standards and technology that will make NNEW possible.
Actions:
2009–2013 – Build and test the first operational version of NNEW by 2013 working collaboratively with the FAA, NOAA and MIT Lincoln Laboratories (LL) to ensure open standards and commonly agreed on technology for a global four dimensional "data cube."
Targeted Sponsors: FAA, DoD, NOAA, NASA
Anticipated Collaborators: MIT/LL, Center for Advanced Aviation Systems Development (CAASD), Commercial airlines
Specific Measurements of Success: Initial Operational Capability of the 4D Data Cube by 2013, including 0-6 hr forecasts of summer and winter storms, turbulence, icing, and ceiling/visibility.
Frontiers
Probabilistic Forecasts Supporting Air Traffic Management (2009–2013)
Through collaboration with NASA and the community of aviation weather users, we are learning how to translate ensemble storm forecasts into probabilistic information of airspace capacity available to the air traffic system when impacting weather is expected. This is information that aviation planners may use in the future to provide for a more orderly flow of air traffic, without actually having to look at or try to interpret weather forecasts. RAL will expand efforts in this area, by incorporating more sophisticated analysis techniques and also by applying them to real–world conditions. Exploration of similar approaches to other aviation weather hazards, such as turbulence and in–flight icing, will be conducted as well.
Actions:
Targeted Sponsors: FAA, NASA.
Anticipated Collaborators: MITRE, commercial airlines.
Specific Measurements of Success: Initiation of an R&D program in 2009; demonstration of a successful integration effort in 2013.
Detection and Transport of Volcanic Ash (2011-2013)
Due to the extreme vulnerability of aircraft to volcanic ash, NextGen has a requirement for detection and forecasting of ash clouds for incorporation into NNEW to drive the air traffic flight planning process.
Actions:
Define and validate the specific requirements of the 4D Data Cube for volcanic ash forecasts. Develop a plan for a 2016 capability that will meet as many of the requirements as are feasible. Work with the community of users to argue the funding of this effort within NextGen budgets.
Targeted Sponsors: FAA, DoD, NASA.
Anticipated Collaborators: Volcanic Ash Advisory Centers, commercial airlines, MITRE.
Specific Measurements of Success: Initiation of an R&D program by 2013.
Space Weather Support for Aviation (2009-2013)
In NextGen, the air transportation system can be adversely impacted by space weather events. The volume of polar flights is projected to increase. NextGen will rely on satellite–based systems for communication, positioning, navigation, timing, and surveillance. A real–time forecast of the impact of space weather events along a particular route of flight is critical to system safety. Furthermore, it is becoming clear that there can be health hazards to flight crews who are repeatedly exposed to the higher than normal radiation levels inherent in flights along polar routes. A real–time forecast of human health effects along a flight path is needed. This capability will require the completion of research efforts and algorithms.
Actions:
Targeted Sponsors: FAA, DoD, NASA, NOAA.
Anticipated Collaborators: Commercial airlines, Mitre/CAASD, High Altitude Observatory, various universities
Specific Measurements of Success: Initiation of an R&D program by 2013.
Environmental Forecasts (2010–2013)
Real–time mitigation of environmental impacts of aviation requires an understanding of those environmental impacts and their dependencies on real-time weather. NextGen's fully operational predictive models and current weather observations will be fused to provide a consolidated probabilistic environmental forecast that is available to users over a Network–Enabled Infrastructure. This capability will build on a body of research and algorithms that will forecast real–time noise propagation, dispersion of airborne pollutants (including from a terrorist attack or accidental release), and forecasts of the sensitivity of atmospheric volumes to exhaust emissions, including greenhouse gases and formation of cirrus clouds.
Actions:
Targeted Sponsors: FAA, DoD, NASA, NOAA.
Anticipated Collaborators: FAA, DoD, NASA, NOAA, airlines, Mitre/CAASD, ESSL.
Specific Measurements of Success: Initiation of an R&D program by 2013.