15 Use of TIR from Space in Operational Systems
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are particularly useful for extreme shallow water coverage and to measure SST close
to coasts. Issues remain, however, for the most effective way to cloud-clear and
calibrate close to coasts.
Geostationary satellites, in clear-sky areas, provide a measure of the diurnal variation more effectively than SST products derived from polar-orbiters, which only
observe at the same time or two each day. Observations of diurnal variation of SST
are necessary to accurately monitor thermal stress on coral (Maturi et al., 2008).
Current techniques use a single nighttime image to represent the SST for each day.
Given that the coral is sensitive to absolute maximums, as well as thermal exposure
(over time), a bleaching prediction technique based on full diurnal observations of
SST (Leichter et al., 2006) is superior to the currently used polar orbiter techniques,
which are being updated just once per day (Maturi et al., 2008).
15.8 Numerical Weather Prediction
Numerical weather prediction (NWP) uses current weather conditions as input into
mathematical models of the atmosphere to predict the weather. Sea surface temperature and sea-ice affect the behaviour of the overlying atmosphere and vice versa.
Consequently, NWP systems need to be regularly updated with the latest SST and
sea-ice observations to ensure an accurate forecast. Daily analyses of both SST and
sea-ice extent and concentration are required by many operational NWP systems.
SST affects the formation and subsequent evolution of tropical cyclones, convection
and thunderstorms, cyclogenesis, sea fog and sea breezes. It can also help upper air
forecasters at the World Aviation Forecast Centre to monitor areas more likely to
develop Cumulonimbus activity which can produce significant threat to aircraft.
15.8.1 Use of TIR
Numerical Weather Prediction models commonly use analyses (level 4) of SST as
a boundary condition over the ocean. The US National Weather Service’s Ocean
Prediction Centre and the Tropical Prediction Centre assimilate the GOES SST level
3 products (Table 15.2) into their operational forecast models.
Another use of SST analyses in NWP is for the quality control of satellite atmospheric sounder channels that peak near the ocean surface. Currently, foundation or
blended SST analyses are used, but in 2010 the Australian Bureau of Meteorology
plans to trial the use of real-time, skin SST analyses produced from a combination of foundation SST analyses and a diurnal warming model using NWP forecast
surface winds as inputs (Beggs et al., 2009a). In regions of the ocean experiencing
high insolation and low winds, SSTskin can experience daily variations of up to 6
or more Kelvin. The presence of cloud can also result in anomalously cool SSTskin
measurements from infrared sensors on satellites, and therefore a real-time estimate
of SSTskin can aid in determining if atmospheric sounder profile data close to the
ocean surface is affected by cloud.
263
are particularly useful for extreme shallow water coverage and to measure SST close
to coasts. Issues remain, however, for the most effective way to cloud-clear and
calibrate close to coasts.
Geostationary satellites, in clear-sky areas, provide a measure of the diurnal variation more effectively than SST products derived from polar-orbiters, which only
observe at the same time or two each day. Observations of diurnal variation of SST
are necessary to accurately monitor thermal stress on coral (Maturi et al., 2008).
Current techniques use a single nighttime image to represent the SST for each day.
Given that the coral is sensitive to absolute maximums, as well as thermal exposure
(over time), a bleaching prediction technique based on full diurnal observations of
SST (Leichter et al., 2006) is superior to the currently used polar orbiter techniques,
which are being updated just once per day (Maturi et al., 2008).
15.8 Numerical Weather Prediction
Numerical weather prediction (NWP) uses current weather conditions as input into
mathematical models of the atmosphere to predict the weather. Sea surface temperature and sea-ice affect the behaviour of the overlying atmosphere and vice versa.
Consequently, NWP systems need to be regularly updated with the latest SST and
sea-ice observations to ensure an accurate forecast. Daily analyses of both SST and
sea-ice extent and concentration are required by many operational NWP systems.
SST affects the formation and subsequent evolution of tropical cyclones, convection
and thunderstorms, cyclogenesis, sea fog and sea breezes. It can also help upper air
forecasters at the World Aviation Forecast Centre to monitor areas more likely to
develop Cumulonimbus activity which can produce significant threat to aircraft.
15.8.1 Use of TIR
Numerical Weather Prediction models commonly use analyses (level 4) of SST as
a boundary condition over the ocean. The US National Weather Service’s Ocean
Prediction Centre and the Tropical Prediction Centre assimilate the GOES SST level
3 products (Table 15.2) into their operational forecast models.
Another use of SST analyses in NWP is for the quality control of satellite atmospheric sounder channels that peak near the ocean surface. Currently, foundation or
blended SST analyses are used, but in 2010 the Australian Bureau of Meteorology
plans to trial the use of real-time, skin SST analyses produced from a combination of foundation SST analyses and a diurnal warming model using NWP forecast
surface winds as inputs (Beggs et al., 2009a). In regions of the ocean experiencing
high insolation and low winds, SSTskin can experience daily variations of up to 6
or more Kelvin. The presence of cloud can also result in anomalously cool SSTskin
measurements from infrared sensors on satellites, and therefore a real-time estimate
of SSTskin can aid in determining if atmospheric sounder profile data close to the
ocean surface is affected by cloud.