Do Tropical Cyclones Provide a Look at Past Changes in the Late Summer-Early Fall Jet Stream from Anomalously Low Stable Isotope Ratios in the Southern Greenland Ice Cores?
Abstract
Tropical cyclones have been shown to produce rain and water vapor with anomalously low stable isotope ratios. Detailed examination of tropical cyclones with GOES satellite water vapor images covering Atlantic tropical cyclones for the years 2000 to 2008 show that between 0 and 4 tropical cyclones, after making a transition to extra-tropical cyclones, appear to pass over Greenland and thereby may deposit snow having an anomalously low isotope value. Further investigation using ECWMF data and a European regional model and examination of upper level (850, 700 and 500 mb) surface maps created using NCEP re-analysis data confirm this. From 2000 to 2008 there is a decreasing trend in the number of transitioning tropical cyclones that make it to Greenland. The positioning of troughs in the Rossby waves seems to be controlling this trend. Precipitation over southern Greenland at the Dye 2 and 3 ice sites is sufficiently high that individual transitioning tropical cyclones might leave a detectable isotopic record. Therefore, a record of the characteristics of the late summer-early fall Jet Stream over North America going back perhaps centuries is a possibility.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2009
- Bibcode:
- 2009AGUFM.A13M..05L
- Keywords:
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- 0724 CRYOSPHERE / Ice cores;
- 1041 GEOCHEMISTRY / Stable isotope geochemistry;
- 3364 ATMOSPHERIC PROCESSES / Synoptic-scale meteorology;
- 3374 ATMOSPHERIC PROCESSES / Tropical meteorology