The UMBC Elastic Lidar Facility (ELF) has been operating at the Chesapeake Lighthouse for the months of August-October, 2002, as part of the AIRS-BBAERI Ocean Validation Experiment (ABOVE).  This page provides quicklooks of the 532nm and 1064 nm channels of the ELF.

A note on the data quality.  The ELF data is shown as uncalibrated attenuated backscatter  (range corrected and background subtracted signal).  Further processing will be done to provide calibrated backscatter profiles.  In the mode shown here, ELF is primarily used for identification of the structure of the boundary layer, aerosol profiles aloft, and importantly here, for cloud clearing for the AIRS retrieval process.  Prior to September 6, an APD detector problem made the 1064 nm signals very noisy and non-linear.  These results have been corrected after that date.  Quicklooks are available for two hours for each AIRS overpass (one hour prior to overpass and one hour after).  Overpass time generally is approximately at the 60 minute mark or otherwised marked.  In some profiles, 10 minutes of noise data (no signal to detectors) has been taken for quality assurance purposes.

Quicklooks by date and time (click on thumbnail image for full size):

20030531 : 1546 UTC  

Haze layer 0-3km, descending clouds 10km early 8 km at end

20030601 : 700 UTC  

Calibration in the middle. Strong cloud decks at 1 & 2 km, no apparent cirrus, very strong winds, no successful sonde launches.

20030602 : 743 UTC  

Low clouds early, at op just haze up to 5km, clear night MW, Mars, Draco all visible

20030602 : 1330 UTC  

Haze from 0-6km no clouds, shutdown for helo just before 1500, shutter problem on restart

20030603 : 648 UTC  

Late start, some cirrus ~11km. Some clouds, but mostly a clear night.

20030603 : 1400 UTC  

20030605 : 0636 UTC  

Heavy cloud deck at about 600m, switched to 8s rep rate. The deck is impenetrable.

20030605 : 1739 UTC  

High clouds early, but a low cloud deck at 1-1.5km obscured.

20030606 : 0719 UTC  

The best run so far. Terra op at 03:08 at 1.44 deg. Low wind very cloudy early. Cleared with 14km cirrus for both op's.

20030606 : 720 UTC  

The best run so far. Terra op at 03:08 at 1.44 deg. Low wind very cloudy early. Cleared with 14km cirrus for both op's.

20030606 : 1822 UTC  

Late start. Heavy cirrus at 12km. Haze to 1.5km. Two shutdowns for nearby planes.

20030608 : 1810 UTC  

Hazy and foggy. No clouds.

20030609 : 1853 UTC  

Heavy haze early, couldn't align. The heavy haze cleared out and I restarted. Haze to 2km, no clouds in evidence.

20030610 : 1758 UTC  

Fog early, some clearing by op. No cirrus. Solid clouds at 3km, somewhat transparent by eye.

20030612 : 0737 UTC  

Some haze and fog, getting foggier as the run progressed. Cirrus showed strong return in depol channel.

20030611 : 1840 UTC  

Hazy and on/off cirrus

20030612 : 642 UTC  

Some haze, cirrus. Slightly clearing towards the end of the run

20030612 : 1611 UTC  

Slight haze, occasional cirrus. Sun Photometer data

20030613 : 0724 UTC  

Somewhat clear, VA beach visible. Cirrus and alto. Profile shows cloud layer @ 4000 m that was not easy to verify visually

20030613 : 1828 UTC  

Cirrus and occasional altocumulus. Too much cirrus for sun photometer

20030614 : 0630 UTC  

Rain earlier, but the night was fairly clear aside from cirrus & cirrostratus in front of moon

20030614 : 1558 UTC  

Thick clouds to start, but clearing as the run went on. Nice day to sit on deck.

20030615 : 320 UTC  

Cirrostratus, light winds. This run has the really cool shelf cloud.

20030615 : 1815 UTC  

35 min run before shutdown for rain

20030617 : 700 UTC  

Very low, thick clouds ~300m. Couldn’t punch through. Shutdown for rain @0645

20030617 : 1830 UTC  

Low clouds. Stopped for very light rain @ 18:25

20030618 : 1846 UTC  

Nice run, even got some clear air in there.

20030619 : 648 UTC  

Mid range clouds, mostly stratus. Occasional drop of rain. Shutdown for sprinkles @ 0740

20030619 : 1751 UTC  

Very cloudy, rain earlier. Had to stop for rain

20030620 : 0320 UTC  

Semi cloudy becoming clear. Depol channel died.

20030620 : 731 UTC  

Clear turning into fog. Depol channel still semi dead.

20030620 : 1834 UTC  

Ignore me

20030621 : 0636 UTC  

Ignore me, too

20030621 : 1604 UTC  

Strange profiles

20030621 : 1739 UTC  

Fairly clear

20030622 : 308 UTC  

Very clear, some cumulus over the land

20030622 : 718 UTC  

Milky way visible, almost no clouds for most of the run. Very clear. Very windy

20030622 : 1822 UTC  

Some clouds to start and end the run, but clear in the middle. Windy

20030623 : 0000 UTC  

Some sunset data - hazy

20030623 : 623 UTC  

Cloudy overhead, some stars visible on and off through the night - sunrise data

20030623 : 1727 UTC  

Almost no clouds, a very high aerosol layer

20030624 : 0706 UTC  

No clouds, same aerosol layer. This is pre sunrise to noonish

20030624 : 1809 UTC  

Hazy, no clouds.

20030625 : 1852 UTC  

Clear and lots of aerosol

20030626 : 654 UTC  

Started clear with no clouds. Thin cloud moves in at 06:40

20030627 : 0737 UTC  

very hazy. Thin aerosol layer reaching 6 km

20030627 : 1840 UTC  

Very hazy with clouds toward the end. Shutter was down at 18:55. Lost almost 10 minutes of run

20030628 : 0642 UTC  

Hazy with no clouds

20030628 : 1745 UTC  

Hazy and clods at 8km.

20030629 : 0724 UTC  

Hazy nd cloudy with thunderstorm at the horizon.

20030629 : 1828 UTC  

Clear on top, some clouds at ovest. Horizon clearly visible. Virginia beach visible.

20030630 : 0629 UTC  

Very clear. The rockets were spectacular!

20030701 : 0712 UTC  

20030701 : 1815 UTC  

20030703 : 1140 UTC  

20030703 : 1803 UTC  

Bands of cloud and clear at ~2km. No cirrus visible.

20030704 : 1846 UTC  

Hazy with no clouds. Haze layer 2.5-3 km

20030705 : 0648 UTC  

Hazy, no clouds. Interesting wave action in aerosols.

20030705 : 1751 UTC  

Hazy, no clouds, windy. No polarization return.

20030706 : 0731 UTC  

Stars visible at zenith, but a strong cirrus deck shows in both channels.

20030706 : 1834 UTC  

Very hot and hazy. Cirrus on and off along with a BL that thickened into clouds ~1 km. Problem with depol in 1st part of run

20030707 : 0636 UTC  

Clouds at 1km and 6km. Cirrus shows in breaks at 13 km.

20030707 : 1739 UTC  

Terra op @ 16:04 Zenith=14.50 Dense clouds at 5km and late in the run at 1km. Generator shutdown early in run is apparent in time-series

20030708 : 0636 UTC  

Terra op @ 3:07 Zenith=0.47 Clear except at Aqua op which had a cirrus (contrail?). The cirrus shows clearly in the polarization

20030708 : 1822 UTC  

Cumulus, especially early, some cirrus and other. Faint polarization from cirrus and possibly other - depol is noisy.

08/10/02

08/11/02

08/12/02

08/15/02

08/16/02

08/17/02

08/18/02

08/19/02

08/20/02

08/21/02

08/22/02

08/23/02

08/24/02

08/26/02

09/05/02

       1835UTC  slight cirrus, otherwise clear, variable MBL

09/06/02

       0637UTC    clear at overpass time, problems with interference in APD before overpass

       1741UTC    thick cirrus at beginning, clearing at overpass time, scattered Cu before pass

09/07/02

       0720 UTC    thin cirrus clearing before overpass otherwise clear

       1823 UTC    thick Cu showing up prior to overpass

09/08/02

       0625 UTC  broken Cu at overpass time, Ci aloft, aerosol at 3-4 km

       1728 UTC    No data taken - complete cloud cover and rain

09/09/02

       0708 UTC  Calm before the storm (GUSTAV), clear above 300m, but mess of low broken stratus at top of MBL (250m)

09/12/02

       1841 UTC  Severe clear, interesting marine boundary layer

09/13/02

       0642 UTC  Severe clear

       1746 UTC  Clear, some light cirrus at end of the run

09/14/02

       0725 UTC  Extensive cirrus throughout run, complicated boundary layer

       1828 UTC  "Really overcast", complicated altostratus, very deep and structured continental boundary layer

09/15/02

       0630 UTC  Overcast, multilayer cloud at 500, 1500 and 3000 m

       1734 UTC  "Sorta overcast and a bit hazy(JC)", multilevel altostratus (92506 MMc), 2 mile visibility

09/16/02

       0713 UTC  Humid, some broken low Cu, extensive multilayer altostratus

       1817 UTC Drizzle, no lidar data, followed by heavy rain and lots of bailing

09/17/02

       0618 UTC  Clear except for scattered broken Cu at overpass time, AQUA is at 58 deg zenith angle

09/18/02

       0701 UTC  Extensive cirrus throughout run, boundary layer run (6hrs), overpass at 60 m mark

       1804 UTC  Low, mid and Extensive cirrus throughout run

09/19/02

       0744 UTC  Low cirrus (high alto?) at beginning, clearing near overpass time

       1847 UTC  Broken very low sCud (500 m), OV10 at 30 and 45 min mark, note AQUA overpass is 214 min mark, generally clear period

09/20/02

       0649 UTC  Called clear, cirrostratus deck found on lidar, very thin, would be subvis in daytime

       1752 UTC  Mostly very clear, one annoying horsetail cirrus right at overpass time, GOES8 shows clear

09/21/02

       0732 UTC  Clear for first 30 minutes, then high thin cirrus decks moved in

       1835 UTC  Very clear, slight cirrus more than 30 minutes before overpass, then severe clear,

09/22/02

       0732 UTC  *****Severe clear*****, low level is aerosol at 75% RH

       1740 UTC  Complicated case, dense scattered low (250m) Cu, opening up to alto (3-5 km), clear at overpass time

09/23/02

       0719 UTC  Some light cirrus and a broad altocumulus later in run, clear at time of overpass (x)

       1823 UTC No lidar data, 100% low stratus and extensive altocumulus

09/24/02

       0625UTC 53.5 deg zenith overpass. No lidar data, no sonde, 100% overcast

       1728UTC  Two layers of cirrus, some alto, and a couple of Cu's, pretty cloudy

09/25/02

       0708UTC  Significant cirrus running ahead of Isodore; 50-60% low Cu at 600m

       1811UTC  2.4 deg elev; 100% Ac coverage; Heavy broken low Cu; probably Ci but can't see that high; Shucks!