Logbook Nr. 4
| Polarstern Satellite Logbook Nr. 4 | |
|---|---|
| Region | Central Atlantic |
| Conceptual Model | Northeast Trade Winds |
| Date/Time | 04 May 2012 |
| Longitude/Latitude | 24,3°N / 19,8°W (12:00 UTC) |
| Expedition |
PS79 (ANT-XXVIII/5) 10 April - 15 May 2012 Punta Arenas - Bremerhaven |
Polarstern is sailing in the northeast trade winds under the influence of a subtropical high pressure area. The days often begin with a wonderful sunrise with isolated cumulus clouds.
Figure L4-1: Sunrise in the northeast trade winds.
Copyright: Juliane Hempelt (DWD).
During the day, amidst the brisk tradewinds (wind: 50°, 08 knots) the temperature only rises to 19,5°C around 12:00 UTC. The measurements from the Polarstern fit well with the wind barbs from ASCAT data.
Figure L4-2: 4 May 2012, 12:00 UTC, Dust RBG with the mean sea level pressure and wind information from ASCAT. Source: EUMeTrain.
SYNOP code for 12:00 UTC. DBLK is the Polarstern's call sign.
DBLK 04121 99243 70198 41598 10508 10195 20135 40202 52006 70200 81101
22212 04197 20302 335// 41002
Figure L4-3: 4 May 2012, 12:00 UTC, SST (Sea Surface Temperature). Source: EUMeTrain.
In Fig. L4-3 you see the change in the SST, measured by the geostationary satellite METEOSAT. The Polarstern is now in a cold water current, the "Canary Current".
Figure L4-4: Global ocean surface currents, with the Canary Current marked. Source: Introduction to Tropical Meteorology - COMET Meted.
Fig. L4-4 shows the cold Canary Current. More information about the currents and their influence on precipitation in central Africa can be found in the COMET module Introduction to Tropical Meteorology in the links below.
Links
Cruise reports from all expeditions. Click on Campaign, which you will find in the opening box of every Polarstern Anchor Dot.
http://www.pangaea.de/PHP/CruiseReports.php?b=Polarstern
Introduction to Tropical Meteorology, 2nd Edition (COMET - MetEd)
Information about currents is in chapter 3: Global Circulation
https://www.meted.ucar.edu/training_course.php?id=18
RGB Colour Interpretation Guide, Dust RGB (EUMeTrain)
http://eumetrain.org/RGBguide/rgbs.html?page=1&sat=-1&rgb=Dust+RGB&colour=-1&phenom=-1&recent=false
Training Module: Operational use of RGBs Part 1 (EUMeTrain)
http://www.eumetrain.org/resources/operational_use_rgb.html
Training Module: Operational use of RGBs Part 2 (EUMeTrain)
http://www.eumetrain.org/resources/operational_use_rgb2.html
Webcast: Sea Surface Temperature (EUMeTrain)
http://www.eumetrain.org/resources/sea_surface_temperature_2011.html
Webcast: Scatterometer Winds from ASCAT (EUMeTrain)
http://www.eumetrain.org/resources/scatterometer_winds_2011.html
Webcast: Polarstern and Satellite Data (with ASCAT)
http://www.eumetrain.org/resources/polarstern_and_satellite_data_2012.html