Tag Archives: trade cumulus

Cold pools formed by precipitating trade Cu invigorate new convection

In the sunglint region of the Aqua swath (22:20 UTC, July 19th, during Research Flight 07 of the NSF CSET project), you can clearly see cold pool boundaries in the sea-state. Presumably changes in capillary waves amplitudes associated with different wind speeds are altering the amount of sunglint. I suspect that the mean wind here is pretty light in order to see strong reflections. You can also see a band of new cumulus clouds at the convergence of the outflows.
ColdPools_Sunglint_CSET_RF07

http://map2.vis.earthdata.nasa.gov/image-download?TIME=2015200&extent=-136.62944383592878,25.779981524276558,-135.80766649217878,26.335889727401558&epsg=4326&layers=MODIS_Aqua_CorrectedReflectance_TrueColor,Coastlines,Calipso_Orbit_Asc&opacities=1,1,1&worldfile=false&format=image/jpeg&width=374&height=253

 

Strong scattering from CALIPSO in trade Cu environments

July 6th 2013:

Between 5N-13S there is strong lidar scattering (red colors below). Clouds have tops at 1-2 km. The Worldview image from Terra, including a zoom in on the milky regions seen from a distance, shows that the clouds appear to be small Cu organized in lines. The scattering values below cloud (0.005 /km/sr) would give an extinction of roughly 0.125 /km assuming a lidar ratio for coarse aerosols (e.g. Masonis et al. 2003) of 25 sr. These extinction values extend over a height range of about 1km, giving a total AOD at 532 nm of roughly 0.12, which seems quite large. It is possible that some of the scattering is coming from optically thin clouds, which we found to be very prevalent in the trades (Leahy et al. 2012).

Surface wind speeds do not seem particularly high (7-10 m/s), according to AMSR-2.

Link to CALIPSO quick look for this case

/data/BROWSE/production/V3-30/2013-07-06/2013-07-06_21-47-15_V3.30_2_1.png image missing