ETL Accomplishments

Using Regional Science and Technology Testbeds

Understanding and Describing Boundary Layer Processes

Understanding and Describing the Atmosphere

Using Regional Science and Technology Testbeds to Advance the Transfer of Research to Operations.

ETL maintains a broad suite of ground-based and airborne remote sensing instruments that support local and regional studies of atmospheric, oceanic, and surface processes necessary to advance NOAA's capability to observe, understand, and predict weather, climate and air quality. This instrument suite is now supporting a number of testbed deployments to accelerate the transfer of science and technology into operations.

Selected Accomplishments

Temperature Forecasting: Observations and Model Assessment

NEHRTP model verification website.

ETL evaluated model meteorological fields with observed fields in a multi-laboratory/NWS field study in 2002, revealing problems with cloud-radiation feedbacks in the models and confirming the physical justification for model improvements planned by NCEP. 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. The changes were transferred to the operational Eta model in July 2003 and are now being evaluated by ETL using a special summer 2003 field deployment.

Air Quality Forecasting: Observations and Model Assessment

NEAQS website.

ETL deployed for the first time an ozone and aerosol lidar on the NOAA ship Ron Brown during the 2002 New England Air Quality Study to characterize the processes affecting the vertical structure of ozone and aerosol over the cold ocean. The transport and mixing of pollutants over the ocean is a major issue for evaluation in forecast models for the Northeast. The summer 2004 field program will focus on this issue with enhanced instrumentation on the Ron Brown.

CCOS website.

For the NOAA Health of the Atmosphere field research programs and Congressionally supported studies conducted for the California Air Resources Board, ETL deployed networks of integrated boundary-layer observing systems to observe and characterize important parameters for air quality including the depth and strength of convective vertical mixing, aerosols and ozone, diurnal wind patterns and surface radiation. Based on feedback from NWS forecasters and forecast users, ETL is developing two new web-based tools. The first is a real-time display of convective boundary-layer (CBL) depth derived from the Doppler spectral moments collected by the wind profilers. The second is a wind profiler trajectory tool that will allow users to plot forward or backward trajectories on a map based on the horizontal winds collected by the wind profiler network. These tools will be available for forecasters and research scientists during the 2004 New England Air Quality Study.

Coastal Hydrometeorology: Technology Development, Observations and Application

Snow-level Product.

Developed and demonstrated a new method using boundary layer wind profilers to monitor the snow-level in winter storms on the US West Coast and in New England. Evaluated the use of these data by NWS/WFOs through web-based feedback.
ETL deployed a prototype gap-filling X-band dual-polarization radar to explore its potential for filling gaps in current NEXRAD coverage with much improved measurements of rainfall rates, particularly for watersheds in mountainous regions.
ETL trained NWS river forecasters and meteorologists at COMET training courses in 2002 & 2003.

Users and Benefits

The primary user is the National Weather Service in providing better forecasts of temperature with current models and in preparing for forecasts of air quality with models now being developed for operational use. In the case of the coastal hydrometeorology testbed program, this grew out of a series of shorter-term winter experiments (CALJET, PACJET) that directly involved water managers, emergency managers, flood control agencies, fishermen associations, harbor masters and others. The current plan 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.

Understanding and Describing Processes at the Interface of the Atmosphere with Land, Ocean and the Cryosphere

ETL's long history of boundary layer research grew from the early insights provided by acoustic, optical and radio remote sensing instruments, gaining a major impetus in the mid-1970's with the transfer of the AFCRL boundary layer turbulence team, famous for the Kansas field studies in the 1960's, to the lab and the construction of the Boulder Atmospheric Observatory 300-m meteorological tower. Since that time, our program has expanded with major contributions to climate-relevant parameterizations for air-sea interaction, using NOAA's unique seagoing capabilities, to pioneering new observing capabilities in the polar regions, and to embracing the NWS Science and Technology Infusion Plan that calls for a focus on the boundary layer in "situationally-sensitive" regions, a focus that is particularly important for improving coastal and air quality forecasting.

Selected Accomplishments

Quantifying air-sea transfers of heat, momentum, and CO₂

ETL worked with its Woods Hole partners to foster the development of a CO₂ version of the NOAA/COARE bulk flux algorithm which has now become the standard for estimating CO₂ fluxes over the ocean. This work has been characterized as an important breakthrough by NOAA's Carbon Cycle Program.
ETL collaborated with scientists at the Woods Hole and Australia's CSIRO to develop and update (most recently in 2003) an algorithm to compute air-sea fluxes from bulk meteorological variables. COARE is the most accurate algorithm available and its wide use for weather, climate, and research applications has established it as the global standard (it has been referenced in more than 400 scientific publications).
ETL cooperated with scientists from the University of Washington to obtain the first ever ship-based remote sensing observations of marine stratocumulus clouds as part of NOAA's CLIVAR research program. The measurements included mm-wavelength Doppler cloud radar, Doppler lidar, wind profilers, air-sea turbulent fluxes, radiative fluxes, and balloon soundings.

Advancing the remote sensing on the Earth's land, ocean, and ice/snow surfaces

Soil moisture maps.

ETL developed the first practical airborne techniques for regional mapping of soil moisture, and has demonstrated the first such application of dual C- and X-band radiometry for this purpose. This system was demonstrated in airborne campaigns over Iowa, Alabama, Georgia, and Oklahoma in 2002 and 2003.
NOAA/ETL is the first and only institution that has succeeded in demonstrating two-dimensional mapping of the near-surface ocean wind field using passive polarimetric radiometry. The ETL effort in this area has been in direct support of the NPOESS Integrated Program Office on the development of the passive polarimetric wind vector concept, scheduled to be used on board the first NPOESS satellite in 2009.
ETL developed an airborne Lidar for fishery surveys. ETL has demonstrated good agreement between LIDAR data and echo-sounder data in tests on epipelagic fishes in the Gulf of Mexico, off Florida, and in the Gulf of Alaska, juveniles of a number of species in the Atlantic off the Iberian Peninsula, mackerel off Norway, and zooplankton in Prince William Sound, Alaska. An imaging capability has been added that allows individual salmon to be identified and counted.
ETL developed a new high-resolution, multi-sensor, blended satellite sea surface temperature (SST) data set that combines the through-cloud measurement capability of microwave sensors with the high accuracy and resolution of infrared sensors.

Users and Benefits

The major beneficiary of ETL's air-sea interaction program has been the global climate modeling community with secondary use of the parameterizations now occurring in NCEP weather models. ETL's program in airborne remote sensing and multi-sensor products benefit NOAA's other line offices including NESDIS and NMFS.

Understanding and Describing the Atmosphere: Weather, Climate, and the Processes That Connect Them

The ability to observe and diagnose the state of the atmosphere for weather and climate applications has been greatly enhanced by ETL's development of remote sensors. For example, ETL's leadership in developing cloud and radiometric remote sensing gave rise to many of the commercial remote sensors now deployed at the DOE's Clouds and Radiation Testbed site. ETL's demonstration of the value of wind profiler networks in Colorado motivated the creation of the Profiler Demonstration Network in the U.S. mid-west. ETL's experience in deploying remote sensing systems in remote areas of the oceans and polar regions will underpin decisions for the next generation global observing system. In addition, ETL's observational and diagnostic capability will support new efforts in understanding processes and impacts that lie between weather and climate time scales.

Selected Accomplishments

Improving Arctic Climate and Weather Forecasting

Developed state-of-the-art radars, radiometers and flux systems that are Arctic hardened and capable of operational monitoring as well as portable field operations together with creating retrieval techniques to blend data streams from multiple sensors to determine atmospheric properties that can not be determined from one system alone. ETL is leading the effort to establish the first SEARCH Arctic Observatory site.

Arctic Retrievals

Generated multi-year, archived data sets of cloud macro and microphysical properties, boundary and surface-layer structure and turbulent exchanges, and surface energy budgets for coastal Arctic and Arctic Ocean locations.
Improved a hierarchy of forecasting (e.g. ECMWF), climate (e.g. CCCMa, CCSM) and regional (e.g. ARCSYM, MM5) models with new observation-based parameterizations as well as providing unique data sets for model validation.

Observing and Modeling Clouds, Aerosols and Radiation

Using a unique combination of remote sensors and models, ETL has engaged in a study of the aerosol indirect effect. Observations are provided by surface-based remote sensors developed at ETL and enable simultaneous profiling of aerosol entering clouds (measured by lidar) and cloud drop response (derived from radar and microwave radiometer). Our models include detailed representation of aerosol and cloud microphysics and the effect of aerosols on cloud drop number and size, and cloud reflectance.
ETL fabricated and is testing a prototype Ground-based Remote Icing Detection System (GRIDS) to remotely identify hazardous in-cloud aircraft icing conditions and issue warnings to pilots and air traffic controllers. This system, being developed for the NWS and FAA, is based on a number of microwave and radar technologies pioneered at ETL.
To solve the problem of assimilating passive microwave data into forecast models over heavy clouds, ETL has developed fast discrete ordinate radiative transfer model routines that provide the Jacobian between the observed brightness temperature and all NCEP prognostic parameters. This program uses ETL's unique theoretical expertise in radiative transfer and numerical weather modeling.

Exploring Issues at the Interface Between Weather and Climate

ETL Played key role in developing the international THORPEX effort that has now been transferred with staff to OAR HQ.
Developed the Weather Climate Connection effort with CDC, with initial results documenting watershed-scale sensitivity to large-scale flow patterns influenced by tropical forcing, and exploring the climatology of atmospheric rivers and their role in linking the tropics and land-falling west coast storms.

Users and Benefits

Observations and diagnostic activities in the polar regions are critical to observing and diagnosing climate change, validating new polar satellite data products, and supporting NOAA's SEARCH efforts. Other efforts support the CCSP as well as the activities of the USWRP, NASA/NOAA Joint Center for Satellite Data Assimilation (JCSDA), and NOAA/NWS/NCEP/EMC, and NWS aviation forecast validation.