U.S. Air Quality

Smoke layers

We received a lot of smoke today. Smoke is visible in both the ELF (top) and DABUL (bottom) LIDAR profiles. It is clear and sunny with high clouds around 12km from ~14:00 to ~17:00(UTC) (see DABUL image). Referring to the Lidar data from DABUL, we know that we began to get a little bit of smoke at ~00:00(UTC) at ~6km, then it became more obvious from ~06:00(UTC) at ~5km, which eventually decreased to ~2km as the day progressed. We received another layer of smoke, this time much higher, at ~10km around 09:30(UTC). The altitude of this layer also decreased and finally merged into the lower layer of smoke. HYSPLIT suggests that the air masses came from the Northwest of UMBC. The boundary layer extends to ~1.8km, and aerosol optical depth went from ~0.2 in the morning to ~0.5 in the afternoon (source: AERONET, GSFC). The hourly PM 2.5 concentrations, from Maryland's Department of the Environment (MDE) Oldtown site in Baltimore, were in the range of 6.8 to 17 ug/m3.

* The hatch was closed from ~03:00(UTC) to ~13:00(UTC) and explains the relative backscatter color scale difference noticed in the DABUL image.

Posted by li at August 14, 2007 11:55 PM