The Doppler Wind and Temperature Sounder (DWTS): enabling next-generation weather and space weather forecasts

Over the last decade it has been established that medium-to long-range weather patterns are significantly affected by stratospheric events, and it is well known that the severe storms are critically dependent on the winds aloft(1-5). However, existing observations of the dynamical atmosphere above the cloud tops are sparse and irregular, and remote measurements of upper atmospheric winds have historically proved challenging. Current numerical models must rely on data from widely separated land-based instruments and satellite observations with modest precision and coverage. Even less plentiful are observations of the neutral atmosphere above 100 km, despite the high potential impact of space weather on global navigational and electrical systems. We present here a new instrument concept, the Doppler Wind and Temperature Sounder (DWTS) that will enable global daily measurements of winds and temperature from 15 to 250 km with fine vertical and horizontal sampling. The measurement concept leverages the high spectral resolution inherently available with gas-filter correlation radiometry. By exploiting the Doppler shifts resulting from a limb-viewing low Earth orbit satellite, DWTS spectrally resolves large ensembles of atmospheric emission features. From this, we are able to extract horizontal wind vectors and kinetic temperature with unprecedented precision. Here we review the DWTS measurement concept, present simulation results, and conclude by describing a low-cost operational system that would quantify atmospheric dynamics from the lower stratosphere into the mid thermosphere for the first time.