Scientific Needs for Weather

• Weather Observations, Forecasts and Warnings

• Weather Prediction

• QPF

• Landfalling Hurricanes

• Coastal Meteorology

• Mountain Meteorology

• Urban Meteorology

Weather Observations and Forecasts and Warnings - 1(Emanuel et al. 1995 and Dabberdt and

Schlatter 1996)

Scientific needs Convective storms

Deep convective downdraft processes Cloud microphysical processes Cloud ice properties Entrainment Land-surface-atmosphere interactions

Atmospheric electricity

Weather Observations and Forecasts and Warnings - 2

(Emanuel et al. 1995 and Dabberdt and Schlatter 1996)

Scientific needs Extratropical cyclones Understand mesoscale phenomena Gravity waves Slantwise convection Development and evolution of frontal cyclones

Potential vorticity Role of tropopause in atmospheric dynamics Aviation weather Better understanding of mesoscale phenomena Thunderstorms Fronts Clear-air turbulence Wind shear Icing

Weather Observations and Forecasts and Warnings - 3

(Emanuel et al. 1995 and Dabberdt and Schlatter 1996)

Scientific needs Modeling fire weather Seasonal climate prediction

Low-frequency oscillations Influence of hurricanes on low-frequency coupled atmosphere-ocean and atmosphere-land surface External influences, such as volcanoes and solar output

Data assimilation techniques for operational datasets

Weather Observations and Forecasts and Warnings - 4

(Emanuel et al. 1995 and Dabberdt and Schlatter 1996)

Observational needs Maintain operational rawinsonde network Improved measurements of temperature, liquid and ice in cloud Microphysical measurements, particularly within ice clouds Improved water vapor measurements WVSS on commercial aircraft GPS DIAL Raman lidars Radiosondes Dropsondes Infrared spectrometers Microwave radiometers Unpiloted aircraft Satellite radiances

Weather Observations and Forecasts and Warnings - 5

(Emanuel et al. 1995 and Dabberdt and Schlatter 1996)

Observational needs Measurements of the maritime atmosphere Ocean fluxes Global observing systems Targeted, adaptive observations Better observations over the mountainous West

Wind profilers Wind and temperature profiles upwind Enhanced mesoscale observations

Weather Observations and Forecasts and Warnings - 6

(Emanuel et al. 1995 and Dabberdt and Schlatter 1996)

Observational needs Better observations over the eastern N. Pacific Profiles of wind, temperature and humidity GOES rapid scan Dropsondes from commercial or military aircraft Altitude-controlled balloons Unpiloted aircraft Buoys Profilers on buoys Satellite radiometric measurements Moisture profiles combined with wind measurements WVSS on commercial aircraft GPS techniques Eye-safe Raman lidars Fourier transform infrared radiometry (like AERIs) Wind profilers WSR-88D radars

Weather Observations and Forecasts and Warnings - 7

(Emanuel et al. 1995 and Dabberdt and Schlatter 1996) Observational needs Better measurements for initial conditions Surface temperature and albedo Soil classification Soil moisture Snow distribution Vegetation SST Sea ice distribution Wave state Ocean color for tracking currents Airborne radars for process studies Aircraft in-situ measurements for downdraft process studies Polarimetric radars for QPF Bistatic radars Joint radar and lightning measurements Ultimate objective Benefit to society

Weather Prediction (Emanuel et al. 1997)

Scientific needs Physical mechanisms of rapidly growing weather systems Observational needs Observations in data sparse regions Automated rawinsondes Ship measurements Profilers on ships Moored and drifting buoys ACARS Piloted and unpiloted aircraft Automated floating devices Passive satellite measurements Global winds derived from sequential satellite imagery Sea-surface winds from scatterometers GPS soundings of temperature and moisture Lidar wind measurements from satellite

Ultimate objective Benefit to society

QPF - 1 (Fritsch et al. 1998)

Scientific needs Process and climatological studies New design for data-gathering strategies for model initialization Define probabilistic framework for precipitation forecasting and verification Development of advanced ensemble techniques Better understanding of storm lifecycle, especially MCCs Better understanding of cloud microphysics PV anomalies Surface boundaries Orographic influence Improved precipitation estimates in 4DDA Assimilate WSR-88D Forecast validation Land-surface-atmosphere interactions

QPF - 2(Fritsch et al. 1998)

Observational needs Improved accuracy and resolution of precipitation observing system Mobile radiosondes Portable lidars Mobile radiometers Improved moisture measurements Stability profiles In situ aircraft observations Land surface measurements Polarimetric radars Satellite estimates Rain gauges Ultimate objective Benefit to citizens, governments, agriculture and businesses “Precipitation is the most important atmospheric variable to forecast”

Landfalling Tropical Cyclones - 1(Marks and Shay 1998 and Emanuel et al. 1995)

Scientific needs – Improve physical understanding and provide better initial conditions Hurricane motion – increased skill Intensity change – poor skill Atmospheric and oceanic boundary layers Air-sea coupling mechanisms Tropical cyclogenesis

Landfalling Tropical Cyclones - 2(Marks and Shay 1998 and Emanuel et al. 1995 and

Rotunno et al. 1996) Observational needs Mobile observing system in a translating storm-coordinate system, including: Satellites Satellite-borne sensors Sea surface scatterometers Special Sensor Microwave Imager Passive water vapor measurements Active radar Active lidar Piloted and unpiloted aircraft from boundary layer to 20 km Expendables from aircraft Fixed and mobile coastal platforms Moored and drifting platforms Expendable bathythermographs Ultimate objective Real-time analyses of storm surge, winds and rain Improve warnings Provide local areas with info before, during and after landfall

Coastal Meteorology and Oceanography - 1 (Rotunno et al. 1996 and Emanuel et al. 1995)

Scientific needs Coastal weather prediction Air-sea fluxes and boundary layer structure in areas of mesoscale variability and at high wind speeds Improved air-sea models of coastal zones Understanding sea ice formation Coastal flash flood forecasting Polar lows

Coastal Meteorology and Oceanography - 2 (Rotunno et al. 1996 and Emanuel et al. 1995)

Observational needs Measurements in ABL and upper-ocean mixed layer Measurements of air-sea fluxes and boundary layers in presence of ice formation Onshore and offshore profilers Satellite data of Special Sensor Microwave Imager (SSMI) Ocean wave spectra and winds from scatterometers and SARs Precipitation Snow cover Sea ice coverage and thickness TPW SST

Coastal Meteorology and Oceanography - 3 (Rotunno et al. 1996 and Emanuel et al. 1995)

Observational needs Depth of thermocline UAVs over oceans from boundary layer to upper levels Moored and drifting buoys measuring ocean fluxes Radars Upper ocean current sensors Minimeteorological drifters Polar measurements of humidity and radiative fluxes

Ultimate objective 4-D VAR Improved forecasts for more than 50% of US population

Mountain Meteorology - 1(Smith et al. 1997 and Emanuel et al. 1995 and

Dabberdt and Schlatter 1996) Scientific needs Modeling topographic circulations Rocky Mountain lee-side phenomena Lee-side cyclogenesis Cold air outbreaks MCSs Trapping of cold air in basins and valleys Orographic precipitation and flash floods Generation of PV over mountains Collective and multiscale effects of complex terrain (continuum of scales)

Mountain Meteorology - 2(Smith et al. 1997)

Observational needs WSR-88Ds Polarimetric radars Profilers and RASS Doppler lidars 3-D, time-varying observations of multiscale orographic flows Satellite sensors Special Sensor Microwave/Imager (SSM/I) Synthetic Aperture Radar (SAR) Sun-glint observations Visible imagery Water vapor imagery Sounding capabilities GPS and sounding combinations to get temperature and water vapor profiles Global wind measurements

Ultimate objective Benefit to society

Urban Weather - 1(Dabberdt et al. 2000)

Scientific needs Impacts of visibility and icing on transportation Winter storms Convective storms Lightning Air quality and toxic releases Integrate multiple datasets into models Explicit use of cloud-resolving models Inadvertant urban convective storm modification Forecast uncertainty quantification

Urban Weather - 2(Dabberdt et al. 2000)

Observational needs Detection of low-visibility and icing conditions Radar precipitation estimates in winter regimes Location of mixed-phase precipitation Quantitative forecasts of frozen/freezing precipitation GPS integrated precipitable water and refractive index profiles ACARS in-situ measurements Boundary layer winds, stability and convergence lines Ultimate objective Benefit to society living in urban areas