Why So Dry? Ocean Temperatures Alone Don't Explain Droughts

Science News ^ | 2-9-2007 | Patrick L Barry

[bcsco]

Note for later reading.

[ROLF of the HILL COUNTRY]

"...new finding suggests that the causes may be more complex than many have supposed..."

Duh, You Think?

[syncked]

"The western United States continues to struggle with the worst dry spell since the 1930s..."

70 years ago, and the awful CO2 has been rising all along, or so they say. Why then haven't the droughts, caused by rising temperatures, been at least consistent, if not worse? What was once the Dust Bowl should now look like the Sahara.

[etlib]

Droughts and deserts are caused by a lack of precipitation. High temperature is not the cause. Some of the wettest areas on earth are also the warmest. Some of the driest areas are also the coldest.

Global warming does not imply world wide drought except in the mind of those wanting to increase the alarm. What with all that melted ice there could likely be more moisture in the air and more precipitation.

[blam]

" What with all that melted ice there could likely be more moisture in the air and more precipitation."

Yes. Ice Ages are very dry events.

[GATOR NAVY]

So, the earth can suddenly have temperatures "3 degrees centigrade warmer than today, on its own, lasting between 1000 A.D. and 1300 A.D, but here in 2007 A.D it can only be man made?????

Yes. And if you have a problem with that, you're no better than a Holocaust denier. /sarc

[Carry_Okie]

IMO this drought is in part man-made.

Grazing regulations have induced a monoculture of over-mature sage that precludes grass cover. The pebbly surface adsorbs IR and rejects water, where the grasses used to reflect IR, transpire water in the day and collect it at night. That changes the entire water cycle over a distance of a thousand miles.

[blam]

And, the buffalo didn't do that when they were there?

[Kevmo]

BFLR

[Carry_Okie]

And, the buffalo didn't do that when they were there?

Bison were a relatively recent introduction, driven over the land bridge in the late Pleistocene. The wolves probably came with them.

IIRC, for the most part, the buffalo herds weren't in the Great Basin and across New Mexico; they were further north. As you may recall, the great herds of the early 19th Centry may have been an aberration due to a human epidemic. When the Great Basin was first settled by white folks, the usual treatment was a nearly ideal combination of sheep and cattle. They browsed down the sage and reduced its production of pre-emergence hormones that suppress the grasses and forbs.

[blam]

" As you may recall, the great herds of the early 19th Centry may have been an aberration due to a human epidemic."

Yes. Okay.

[I got the rope]

BTTT...good one.

[oneolcop]

Isn't it also true that bison ate plants that "modern" ranchers consider "weeds" along with migrating thereby avoiding overgrazing any particular part of their range?

[SunkenCiv]

Note: this topic is from 2/09/2007. Thanks blam.

· join · view topics · view or post blog · bookmark · post new topic · subscribe ·

[SunkenCiv]

· GGG managers are SunkenCiv, StayAt HomeMother, and Ernest_at_the_Beach · · join list or digest · view topics · view or post blog · bookmark · post a topic · subscribe ·
	Antiquity Journal  & archive  Archaeologica  Archaeology  Archaeology Channel  BAR  Bronze Age Forum  Discover  Dogpile  Eurekalert  Google  LiveScience  Mirabilis.ca  Nat Geographic  PhysOrg  Science Daily  Science News  Texas AM  Yahoo  Excerpt, or Link only?	Note: this topic is from 2/09/2007. Thanks blam. Researchers recently pieced together the most comprehensive history yet of drought in the Great Plains region. The record covers the 10,000 years since the end of the last ice age. This new time line shows three distinct megadroughts—periods of severe dryness lasting for centuries. Scientists often attribute drought to changes in ocean-surface temperature patterns, such as those associated with El Niños. But when the research team compared its record with estimates of historical sea-surface temperatures, only the most recent of the three dry spells matched up... the scientists found a 300-year dry period that began about 1,000 years ago, coinciding with a well-known warm episode called the Medieval Climate Anomaly. They found two other epochs of desertlike conditions that ran from 4,500 to 2,300 years ago and from 9,600 to 6,500 years ago. Blast from the Past. Just adding to the catalog, not sending a general distribution. To all -- please ping me to other topics which are appropriate for the GGG list.
· History topic · history keyword · archaeology keyword · paleontology keyword · · Science topic · science keyword · Books/Literature topic · pages keyword ·