WIVERN
A WInd VElocity Radar Nephoscope for observing global winds, clouds and precipitation
About WIVERN
Accurate weather forecasts are important to our daily lives, and in particular in support of emergency management during severe weather events. Wind, cloud and precipitation belong to the fundamental variables in NWP models, and the World Meteorological Organization (WMO) has defined in particular the lack of globally distributed direct wind observations as one of the main deficits of the current WMO Global Observing System. WIVERN will be the first space-based mission to provide in-cloud winds, and hence contribute to filling the gap in the current WMO Global Observing System to the benefit of NWP and climate research. WIVERN will also provide high-resolution reflectivity profiles of rain, snow and ice water, which can be used to achieve a better quantification of the Earth’s hydrological cycle and energy budgets, given the significant reduction in sampling errors compared to current and future cloud radar missions.
Mission objectives
- To extend the lead time of useful prediction skills (including high-impact weather) by assimilation of wide-swath winds from clouds, and profiles of radar reflectivity of clouds and precipitation, into numerical weather prediction (NWP) models.
- To establish a climate record of cloud profiles, global solid/light precipitation, and, innovatively, winds, crucial for a better quantification of the Earth’s hydrological cycle, and energy budgets, with a significant reduction in sampling errors of current and planned cloud radar missions.
- To improve numerical models by providing new metrics and observational verification to assess different NWP parameterisation schemes within such models. NWP and climate models use similar schemes so better NWP models will also augment confidence in climate models.
Instrument
WIVERN concept: a dual-polarization Doppler conically scanning 94 GHz radar measuring line-of-sight winds and reflectivity profiles with 640 m vertical resolution, an 800 km wide swath and an average global revisit time of 1.5 days (equator) and 1 day (> 50°lat.). The CloudSat climatology of cloud reflectivities predicts that between one and two million winds should be observed each day that satisfy the WMO “goal” of 2 m/s precision.
