Quantifying the Depth of the Boundary Layer Using Two Independent Satellite Products
Abstract
Subtle shifts in the height of the marine inversion overlying stratiform clouds can lead to changes in the thermodynamically driven circulations sustaining the clouds, altering the aerosol and moisture sources, affecting precipitation and cloud lifetime. Recent advances in observing technology allow us to quantify the height of this layer in greater detail than ever before. Two independent datasets are introduced and compared here: One is created using radio occultation between COSMIC GPS satellites that is observed when the satellite-to-satellite line-of-site passes through the hydrolapse at the inversion top. The other is based on multiple A-Train satellites (CALIPSO and MODIS) and uses cloud tops in the eastern subtropical oceans as a proxy for PBL depth for cloud amounts greater than 30%. PBL depth is approximated using the difference between cloud top and sea surface temperature assuming a parameterized lapse rate. The COSMIC product offers global coverage, but with irregular and inconsistent temporal resolution while the A-train product offers coverage of only the eastern subtropical stratocumulus regions, but is available twice daily at regular intervals. A comparison of these independent datasets in overlapping regions shows similarities in seasonal cycles and sub-seasonal variability, allowing for the creation of vastly improved global and local climatologies of boundary layer depth.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.A43B0216E
- Keywords:
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- 3305 Climate change and variability;
- ATMOSPHERIC PROCESSESDE: 3307 Boundary layer processes;
- ATMOSPHERIC PROCESSESDE: 3310 Clouds and cloud feedbacks;
- ATMOSPHERIC PROCESSESDE: 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSES