Satellite-Based TC Surveillance: Status and Future Needs

Tropical cyclone (TC) monitoring relies heavily on satellite remote sensing due to the temporal and spatial requirements that exist within the typically data sparse oceanic environments. Although TCs are viewed as being large systems, our ability to measure the critical storm attributes (maximum sustained winds and radius of hurricane, storm and gale winds) with in-situ observations is woefully inadequate due to severe sampling limitations and high potential costs. Thus, the global community has incorporated a constellation of satellite sensors to carry out 24/7 TC monitoring in a successful collaborative effort.

TC remote sensing is currently at a peak in three regards: 1) the geostationary constellation is relatively mature and stable with more than five satellites spaced around the globe and operated by multiple countries/organizations with data freely shared, 2) we now have the highest number of passive microwave imagers available due to the wealth of research and operational DMSP satellites still functioning well past their prime, and 3) microwave sounders from numerous platforms are enabling the TC warm core measurements needed to ascertain intensity estimates. In addition, we have three functioning scatterometers (QuikSCAT, ASCAT and partial ERS-2) as well as the TRMM precipitation radar, the CloudSat cloud radar and Calypso that provide their own unique capabilities.

The future of TC remote sensing has multiple threads:

1) the geostationary community will see a rapid increase in new satellites/sensors over the Indian Ocean and western pacific and when GOES-R come online, enhanced temporal, spatial and spectral characteristics will lead to improved products,

2) the next few years will likely see a rapid decline in the temporal sampling from microwave imagers as research and operational sensors fail due to age, and

3) NPOESS launch delays may increase temporal sampling data gaps needed to monitor TCs.

Fortunately, multiple discussions highlighting new opportunities that would significantly advance TC monitoring capabilities are in progress: XOVWM, HIRAD, GeoSTAR, NIS, and will be discussed in following presentations.