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Klaatu_Nicto #361 Posted Sep 24 2020 - 04:01

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Block Quote

 

Pre-1800

There are indications for megadroughts between 900 and 1300.[16] Drought apparently struck what is now the American Southwest back in the 13th century, which probably affected the Pueblo cities, and tree rings also document drought in the lower and central Mississippi River basin between the 14th and 16th century. The droughts of that period might have contributed to the decline and fall of the Mississippian cultures.[17]

 

The 18th century seems to have been a relatively wet century in North America, but there were apparently droughts in Iowa in 1721, 1736, and from 1771 to 1773.[18]

 

19th Century

There were at least three major droughts in 19th-century North America: one from the mid-1850s to the mid-1860s, one in the 1870s, and one in the 1890s.[17][19] There was also a drought around 1820; the periods from 1816 to 1844 and from 1849 to 1880 were rather dry, and the 19th century overall was a dry century for the Great Plains.[20] While there was little rain-gauge data from the mid-19th century in the middle of the US, there were plenty of trees, and tree-ring data showed evidence of a major drought from around 1856 to around 1865. Native Americans were hard hit, as the bison they depended upon on the Plains moved to river valleys in search of water, and those valleys were full of natives and settlers alike. The river valleys were also home to domestic livestock, which competed against the bison for food. The result was starvation for many of the bison.

 

The 1870–1877 drought brought with it a major swarm of Rocky Mountain Locusts, as droughts benefit locusts, making plants more nutritious and edible to locusts and reducing diseases that harm locusts. Locusts also grow more quickly during a drought and gather in small spots of lush vegetation, enabling them to swarm, facts which contributed to the ruin of much of the farmland in the American West. The evidence for this drought is also primarily in tree-ring, rather than rain gauge, data.

The 1890s drought, between 1890 and 1896, was the first to be widely and adequately recorded by rain gauges, with much of the American West having been settled. Railroads promised land to people willing to settle it, and the period between 1877 and 1890 was wetter than usual, leading to unrealistic expectations of land productivity. The amount of land required to support a family in more arid regions was already larger than the amount that could realistically be irrigated by a family, but this fact was

made more obvious by the drought, leading to emigration from recently settled lands. The Federal government started to assist with irrigation with the 1902 Reclamation Act.[19]

 

1930s

The Dust Bowl or the Dirty Thirties was a period of severe dust storms causing major ecological and agricultural damage to American and Canadian prairie lands from 1930 to 1936 (in some areas until 1940). The phenomenon was caused by severe drought coupled with decades of extensive farming without crop rotation, fallow fields, cover crops or other techniques to prevent erosion.[21]Deep plowing of the virgin topsoil of the Great Plains had displaced the natural grasses that normally kept the soil in place and trapped moisture even during periods of drought and high winds.

 

During the drought of the 1930s, without natural anchors to keep the soil in place, it dried, turned to dust, and blew away eastward and southward in large dark clouds. At times the clouds blackened the sky reaching all the way to East Coast cities such as New York and Washington, D.C. Much of the soil ended up deposited in the Atlantic Ocean, carried by prevailing winds which were in part created by the dry and bare soil conditions itself. These immense dust storms—given names such as "Black Blizzards" and "Black Rollers"—often reduced visibility to a few feet (around a meter). The Dust Bowl affected 100,000,000 acres (400,000 km2), centered on the panhandles of Texas and Oklahoma, and adjacent parts of New Mexico, Colorado, and Kansas.[22]

 

Millions of acres of farmland became useless, and hundreds of thousands of people were forced to leave their homes; many of these families (often known as "Okies", since so many of them came from Oklahoma) traveled to California and other states, where they found economic conditions little better than those they had left. Owning no land, many traveled from farm to farm picking fruit and other crops at starvation wages. Author John Steinbeck later wrote The Grapes of Wrath, which won the Pulitzer Prize, and Of Mice and Men about such people.

 

Negative effects included bank closures and overburdened relief and health agencies. Economic migrants also had mixed success as native workers in many areas resented the intense competition for dwindling jobs. The National Drought Mitigation Center has reported that financial assistance from the government alone may have been as high as $1 billion (in 1930s dollars) by the end of the drought.[1]

 

1940s

Drought began in the Southwestern United States in 1944 and continued through the entire rest of the decade; one of the longest recorded droughts observed there. This drought continued into the 1950s.[23]

 

California Reservoirs Rise from Drought to Deluge
April 21, 2017
A five-year drought in California ended spectacularly this winter, with the state emerging from one of its driest periods on record by enduring one of its wettest.
https://earthobserva...ought-to-deluge

 


Edited by Klaatu_Nicto, Sep 24 2020 - 04:02.


GeorgePreddy #362 Posted Sep 24 2020 - 04:09

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View PostHelpless, on Sep 23 2020 - 18:37, said:

u seem triggered to me.....

 

 

How I seem to you is unimportant.

 

You seem clueless to me. Am I right ?

 

 

 

 

 

 

 



Helpless #363 Posted Sep 24 2020 - 04:32

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View PostGeorgePreddy, on Sep 24 2020 - 03:09, said:

 

How I seem to you is unimportant.

 

You seem clueless to me. Am I right ?

 

 

 

 

 

 

 

yup.... ur triggered alright.....

u keep coming in here... only to talk to me.... 



Klaatu_Nicto #364 Posted Sep 24 2020 - 15:33

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Multivariate ENSO Index Version 2


The El Niño/Southern Oscillation (ENSO) - a naturally occurring anomalous state of tropical Pacific coupled ocean-atmosphere conditions - is the primary predictor for global climate disruptions. These can persist over several seasons and thereby produce severe regional effects. An appraisal of the real-time status of ENSO is thus important for a host of climate services that inform societal responses and trigger policy actions for water supply, food security, health, and public safety.


The bi-monthly Multivariate El Niño/Southern Oscillation (ENSO) index (MEI.v2) is the time series of the leading combined Empirical Orthogonal Function (EOF) of five different variables (sea level pressure (SLP), sea surface temperature (SST), zonal and meridional components of the surface wind, and outgoing longwave radiation (OLR)) over the tropical Pacific basin (30°S-30°N and 100°E-70°W).


Key features of composite positive MEI events (warm, El Niño) include (1) anomalously warm SSTs across the east-central equatorial Pacific, (2) anomalously high SLP over Indonesia and the western tropical Pacific and low SLP over the eastern tropical Pacific, (3) reduction or reversal of tropical Pacific easterly winds (trade winds), (4) suppressed tropical convection (positive OLR) over Indonesia and Western Pacific and enhanced convection (negative OLR) over the central Pacific (Fig. 1a). Key features of composite negative MEI events (cold, La Niña, Fig. 1b) are of mostly opposite phase.


Current Value: -1


https://psl.noaa.gov/enso/mei/

 

 

US-Qatar Partnership Aims to Find Buried Water in Earth's Deserts
https://www.jpl.nasa...hp?feature=7753


Edited by Klaatu_Nicto, Sep 24 2020 - 15:38.





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