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Author Topic: When There Is A Drought, Does It Rain More Elsewhere ?  (Read 7082 times)

Offline neilep

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*sheepy bounces into Forum*

"Happy Freeday !!..YAYYY !!"

Dearest Droughtoloigusts,

As a sheepy I of course luff to play in the rain. I do !..there's nothing I like more than to grab my chess board upon seeing the first drop of rain and gather all my friends together from the ' Chess In Rain' club for a game. ...and I don't even play chess !!

Looks, here's some rain !



Nice eh ?

Being delivered next Tuesday


But look at this place...it's needs rain...there's a drought !


A Droughty Place



What I would like to know is that when in times of protracted drought in one place ,does this mean that somewhere else in the world there is more rain than ususal ?

Cos the rain that would normally fall there must go somewhere eh ?

Whajafink ?


Hugs & Shmishes


mwah mwah mwah !!


Neil
The Rain In Spain Falls Mainly On The Plain
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx


 

Offline Don_1

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #1 on: 18/09/2009 11:41:21 »
Hmmm, not a bad question for a wooly transvestite.

I s'pose ifn it doesny fall there, it must fall somewheres else. Probably on me!
 

Offline SkepticSam

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #2 on: 18/09/2009 16:33:24 »
A broad answer would be yes. If we relate this to El Nino events then you can have drought in southeast Asia and northern Australia. westwward can see a failure of the summer monsoon over the Indian subcontinent and even droughts in south and northeastern Africa.

Yet you can have flooding caused by El Nino in places such as California as happened on 1998.

Links:
NOAA el niņo page [nofollow]
Droughts a nd flooding rain [nofollow]
Wetter here fryer there PDF file [nofollow]
 

Offline neilep

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #3 on: 18/09/2009 19:44:25 »
Hmmm, not a bad question for a wooly transvestite.

I s'pose ifn it doesny fall there, it must fall somewheres else. Probably on me!

Thanks Don !

I'll share the downpour with ya chum !  :D
 

Offline neilep

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #4 on: 18/09/2009 19:48:00 »
A broad answer would be yes. If we relate this to El Nino events then you can have drought in southeast Asia and northern Australia. westwward can see a failure of the summer monsoon over the Indian subcontinent and even droughts in south and northeastern Africa.

Yet you can have flooding caused by El Nino in places such as California as happened on 1998.

Links:
NOAA el niņo page
Droughts a nd flooding rain
Wetter here fryer there PDF file


Thanks for the great links SkepticSam...and for the corroboration within your post on what I thought.
 

Offline frethack

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #5 on: 18/09/2009 22:21:54 »
Hmmm.  It is a good question, but it depends on the time scale you are asking.

During cooler periods of centennial/millennial length there is the tendency toward a more arid climate with less overall rainfall.  Warmer periods tend to produce, on the whole, a more humid global environment with higher rates of evaporation and moisture transport.

During the Last Glacial Maximum (between about 23.5 and 17 thousand years ago) very arid climates prevailed and there was mass desertification in many regions of the earth.  Conversely, the Holocene Climate Optimum (~9 to 5 thousand years ago) was generally a very humid, wet period with lakes, rivers, and vegetation throughout a good portion of the Sahara desert.  This has much do to orbital variations (precession/obliquity/eccentricity), but also has a lot to do with very high solar activity.  It would also depend at which latitude you live (high/low pressure belts).

As for distribution of weather systems, I think Paul is best equipped to answer this correctly

 

Offline SkepticSam

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #6 on: 18/09/2009 23:56:15 »
I lost my initial reply, so this may make less sense than when I first thought it...

This could be an is the grass greener on the other side question, on the large scale.

Thinking about this question differently I don't think a single air mass in one location could have such a drastic effect as to cause one area to be in drought and another to be in flood. But on the small scale, measured in days or weeks you can have an air mass or the jetstream not being on it's usual location that can give unseasonal weather to two locations.

If you remember late July or early august last year, you may also remember that the UK had quite a lot of heavy and prolonged rainfall. This was due to the jetstream not being in it's usual location. So the UK was wetter than average and the place the moisture should have ended up (memory draws a blank) was dryer. Not exactly drought and flood on the large scale but one location did suffer flooding and another whilst not in drought was deprived of some of it's seasonal rainfall. For those that enjoy horseracing this was the period when the Ebor meeting was cancelled due to a flooded course for the first tome on it's history.

Other examples of moisture being in the wrong place was earlier this year when the UK experienced heavy snowfall. This was because of two air masses coming together over the UK giving it more precipitation than would be average for the time of year and reducing the precipitation that would have fallen elsewhere.

Whilst this does not answer your question, it does show how the small scale works in part. Of course it's not complete as it does not mention how low pressure systems are diverted from their path by omega highs or blocking highs or other such events.

I suspect that CSIRO has done plenty of research in to this. Why not drop them an email? They always reply and have great customer services.

Links:
Amazon hit by climate chaos. Floods and drought [nofollow]

 U.S. Geological Survey National Water Summary
Water Supply Paper 2375
[nofollow]

predicting the future [nofollow]


Edit: Edited to correct links
« Last Edit: 18/09/2009 23:59:34 by SkepticSam »
 

Offline SkepticSam

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #7 on: 23/09/2009 01:18:48 »
Sorry for coming back again with another different answer. I'm still not sure about droughts causing floods or increased rainfall elsewhere, but droughts can cause droughts.

If you take the sahara for example, then I'm sure we can all agree that there is a drought going on there.

Large volumes of Saharan dust are spread by the wind in all directions and  lands in countries such as the USA and Israel. Not only that but the presence of that dust in the atmospher can lead to reduced rainfall.

There has been analysis of a dust cloud that was blown over Israel in 2000. What this showed was that the large dust particles were acting as condensation nuclei but they were only producing very small cloud droplets and no or very little precipitation would fall from those clouds. Nearby clouds that contained few desert dust ccn had nearly the same amount of water as the clouds with lots of dust and these were precipitating. The dust particles suppress the coalescence of cloud droplets. 

Also large amounts of dust can partially block incoming solar radiation so the land surface in not heating like it should. This leads to a suppression of convection, convection that produces the clouds in the first place. So dust blown from one drought area can lead to a reduction in rainfall and cloud formation in another. A process that could lead to drought in the area the dust was blown to.
 

Offline SkepticSam

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #8 on: 23/09/2009 01:24:21 »
I actually have another answer to this question involving the Azores high and maybe another weather system, but it's possibly too long to tap out on my phone at this time of night. Try and find time tomorrow.
 

Offline SkepticSam

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #9 on: 08/10/2009 21:34:43 »
The more I think of this the more the answer (in the extreme) has to be El Nino. During an El Nino in 1997/8 there was drougth in southern Africa, eastern Australia. Forest fires from heat in indonesia. Droughts in north china  

South California had torrential rain resulting in floods, mud and landslides. Flooding in Peru, Kenya and Africa. Floods in Poland and the czech republic all caused by one El Nino event.    
 

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When There Is A Drought, Does It Rain More Elsewhere ?
« Reply #9 on: 08/10/2009 21:34:43 »

 

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