A substantial amount of precipitation in the midlatitudes occurs in association with extratropical cyclones. Using the data generated by version 1 of the Goddard Earth Observing System (GEOS-1) Data Assimilation System for 198589, hydrologic processes and the water vapor budget over the United States were analyzed to illustrate the maintenance of precipitable water and precipitation associated with extratropical cyclones. The area-mean divergence of water vapor flux covering the Great Plains and the eastern region of the United States (80105W, 3050N) was adopted as a hydrologic index. The cyclones over this region that have values of this index smaller than minus one standard deviation over a season were selected for analysis. On average, 15 cases were selected for each season. The composite results show a developing baroclinic wave coupled with a low-level cyclone in which the low-level convergent (divergent) center and the upper-level divergent (convergent) center ahead of the trough (ridge) are linked by an upward (downward) branch of the divergent circulation, consistent with the classic cyclone model. Thus, water vapor converges (diverges) through the low-level divergent circulation of the cyclone wave to maintain precipitation (evaporation) centers ahead of the trough (ridge). It is estimated that the amount of water vapor accumulating in the Great Plains and the eastern United States throughout winter (NovemberMarch) could be converged by typical cyclones within a month. During summer (MaySeptember), it would take only about half a month for typical cyclones to converge water vapor toward this region sufficient to account for the summer season runoff by streamflow over this region.
Bulletin of the American Meteorological Society – American Meteorological Society
Published: Jul 26, 1996
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.
All for just $49/month
Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.
Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.
It’s easy to organize your research with our built-in tools.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera