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Achievements

• Recent Accomplishments
• Exploring Tropical Origins of Atmospheric Rivers Using the NOAA P-3 Research Aircraft
• Meteorological Equipment Installed In Time for Record Breaking Storm
• Automated Bright-band Height Detection Algorithm

 

Accomplishments

Established a Hydrometeorological Testbed (HMT)

ETL has co-led, with the NWS, the establishment of a collaborative method to improve NOAA's hydrometeorology related service goals, including flash flood warning accuracy and lead time, 24-hour quantitative precipitation forecasting, and winter storm warning accuracy and lead time. The underlying concept is to bring researchers, forecasters and forecast users together to develop, test, evaluate and recommend permanent, cost-effective solutions to limitations in current observing systems, model parameterizations, forecasting techniques, and understanding of key physical processes. The design is based upon experience gained in several programs around the country and in recommendations from several planning activities, including PACJET planning meeting (Oct 2001), USWRP Warm-Season QPF planning workshop (early 2002), NOAA's STIP process (summer/fall 2002), cross NOAA line-office planning meeting (winter 2002). (See HMT and PACJET-2002 hotitems.) .

Some key milestones include:

• Developed and demonstrated new tools: e.g., new method to monitor the snow-level in winter storms on the US West Coast and in New England, e.g.,applications include improved winter storm warning and flooding forecasts. (See Snow level hotitem.)
• Contributed leadership in planning: part of STIP Hydrology and Winter Weather teams, member of NOAA hydrology program planning team in PPBS, Co-lead on NOAA's HMT planning, Co-lead of USWRP Cool-Season QPF planning.
• Evaluated and recommended new methods: acted as "honest broker" for potential solutions to critical gaps in regional observations, e.g., recommend most cost-effective approach to fill gaps in coastal radar coverage.
• Tested Gap-filling radar: ETL deployed a prototype gap-filling polarimetric radar to explore the potential for filling gaps in current NEXRAD coverage using radars that are tailored to cover flood-prone watersheds at low cost, e.g., 3 - 5 gap-filling radars for the cost of 1 new NEXRAD. (See Gap-filling radar hotitem).
• Contributed to NWS forecaster training: NWS river forecasters and meteorologists at COMET training courses in 2002 & 2003. (See NWS Training hotitem.)
• Conducted state-of-the-art research: improve understanding of physical processes, e.g., microphysics, orographic rain, and weather-climate connections. Recent scientific papers on these topics include Neiman et al (2002), White et al. (2003), and Ralph et al. (2003).
• Advised water managers: briefed California water managers on "Strategies for Improving Forecasts" related to flood control, water supply, and endangered species in the American River watershed. Up to $10 B in damages would occur in a 200-year flood, which could be partly mitigated by better forecasts. See Water Management hotitem.)
• Enhanced NOAA Capacity: NOAA's leadership has recommended that NOAA strongly pursue improving its services related to fresh water resource information, including "integrate NOAA's collaborative research, data, and operations to generate products and services to help water resource managers." Implementing this goal requires close coordination between NWS-OAR-NESDIS-NOS-NMFS. The HMT approach is well posed to help achieve these goals.

Helped NOAA improve temperature forecasts to increase US energy security

During the summer of 2002 several NOAA Research laboratories (ETL, FSL, NSSL) collaborated with the National Weather Service, including NECP, on a project to assess and improve forecasts of surface temperature in New England using a regional testbed approach. A number of models were exercised during the summer field study in combination with an extensive surface and upper-air meteorological network.

The motivation for this project was the recognition that the annual cost of electricity on a nationwide basis could decrease by $1 billion per year if the accuracy of surface temperature forecasts improved by 1 degree Fahrenheit, as mentioned in a recent Message to NOAA from Admiral Lautenbacher. During this project arrays of special research grade instruments were deployed throughout New England by NOAA Research, and the measurements from these instruments were compared against predictions made by operational and research forecast models. These models included the Eta model, which is the principal operational regional forecast model used for the United States, the Rapid Update Cycle (RUC) model, and an experimental bias-corrected ensemble in which model biases are corrected by using the history of the model's forecast performance over the previous week.

The summer 2002 project resulted in several changes to the operational RUC model that will improve surface temperature forecasts, and demonstrated that the experimental bias-corrected ensemble preformed equal to or better than the NGM-MOS forecasts, which was the standard used for the experiment.

For the Eta model, the summer 2002 project began at a time when NCEP was already aware of deficiencies in the model regarding surface temperature accuracy, and had modifications to the model planned for implementation later in the year that would correct for these deficiencies. The special field measurements taken by NOAA Research confirmed that the same physical parameterizations within the Eta model known to be causing temperature biases in other regions of the U.S. were also responsible for temperature errors in New England. In addition, these special measurements documented the propagation of the surface temperature errors onto related meteorological phenomena such as the sea-breeze cycle (which can, in turn, affect air quality forecasts). Finally, the special measurements provided insight into what additional instruments would be required during a follow-on summer 2003 field program to more fully evaluate the performance of the key physical parameterizations within the model that most directly affect surface temperature forecasts.

NCEP evaluated its planned modifications to the Eta model during the spring of 2003 and found an improvement of nearly 1.5 F in the forecast maximum daily temperatures for New England, and improvements on the order of 0.5-1.0 F in other regions of the U.S. The changes were transferred to the operational Eta model in July 2003.

During the summer 2003 field program NOAA Research again deployed a special network of instruments to evaluate the accuracy of model physical parameterizations. NOAA Research and NCEP are collaborating on this project, evaluating both the recent changes to the Eta model during their first operational summer season, as well as new parameterization schemes that NCEP has developed for possible future implementation in the Eta model. NOAA Research and NCEP are also evaluating versions of the future Weather Research and Forecast (WRF) model (to replace the Eta in 2005), the GFS model, the RUC model, and 2 experimental versions of the Short Range Ensemble Forecast (SREF) model. NOAA Research is also evaluating its bias-corrected ensemble, which relies on model members from both NCEP and NOAA Research.

ETL, in partnership with OAR/Climate Diagnostics Center and the NWS/Climate Prediction Center Launched NOAA's Weather-Climate Connection Program

This project began in FY2002, expanding NOAA's research on the causes and predictability of extreme weather and climate events. The overall goal is to develop improved national capabilities to predict risks of extreme events, such as major floods, droughts, and cold waves, at lead times from several days to a season. More specifically, this research aims to: 1) improve early guidance to the nation on threats of high impact weather and climate events, such as major floods or cold waves, and 2) better localize the areas of most likely impacts. This research addresses a major gap in NOAA's current operational capabilities between short-range predictions and warnings and seasonal to interannual forecasts. It also directly supports the NWS strategic goal of developing a seamless suite of forecast products ranging from minutes to seasons in advance.

The central hypothesis of this project is that significant improvements in early identification and localization of extreme event threats can be obtained through advances in observing, understanding, and modelling of the links between weather and climate variability. Of particular emphasis are the connections between tropical climate variations and mid-latitude storm systems, and the role of regional physical processes in modulating and localizing impacts. A specific target area for forecast improvements is the U.S. West Coast, where prior research has indicated: 1) a significant connection between tropical Pacific rainfall patterns and the likelihood of flood-producing storms,and 2) the role of orographic and coastal ocean processes in localizing impacts.

ETL-led accomplishments include:

• Documented Watershed-scale sensitivity to large-scale flow patterns influenced by tropical forcing. Watersheds that are adjacent experienced very different degrees of winter flooding during the strong El Nino of 1997/98. Analyses reveal both the causes of this difference (characteristics of the low-level jet within intense extratropical cyclones), and its linkage to ENSO. These results are presented in two formal scientific papers, one in Journal of Hydrometeorology (Ralph et al.) and the other in Journal of Climate (Andrews et al.). These results are of great interest to emergency managers and water resource managers due to the potential of refining decision making to account for more local variations in rainfall, runoff and flooding. These findings have become core elements of NWS forecaster training.
• Explored the climatology of atmospheric rivers and their role in linking the tropics and land-falling west coast storms. Documented the structure of a modest atmospheric river using aircraft and satellite data from CALJET, and analyzed satellite data for the entire 1997/98 winter season. 75% of the meridional water vapor flux was found in narrow plumes roughly 400 km wide, and plays a critical role in extreme rainfall.
• Initiated the collection of a unique new long-term data set. ETL has deployed wind profilers each winter season on the U.S. West Coast to document the low-level jet, which very poorly represented in current data sets, and yet is critical in modulating local rainfall and flooding and more generally in linking changes in ENSO to changes in local extreme weather events. This data set will be the foundation of invaluable long-term records for future weather-climate connection studies.