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Dr Sardonicus 2018-04-05 17:10

It's true that a cloudburst won't soak the ground as well as a long, gentle rain. It's also true that a really bad drought might not be "quenched" by even a prolonged rainy spell. But, of course, the fact that the ground may be dried out to a great depth, and/or aquifers may be depleted, is likely due to a lack of precipitation over an extended period.

Snow usually is beneficial moisture in that it is less apt to run off than a heavy rain. However, it may have trouble soaking in if it falls on really solidly frozen ground. In mountain areas, snow can also evaporate without soaking into the ground. Downslope winds, such as the chinook, become quite hot and dry, and can cause snow to sublime at an incredible rate, sucking it up and leaving the ground dry.

kladner 2018-04-05 21:11

Of course, extreme overuse of ground water is the real reason behind depleted aquifers. More that 30 years ago there were articles in Houston area papers about ground subsidence due to over-pumping. A photo provided to illustrate the problem showed a pump for a deep water well standing on its pipe 10 feet above the ground, which had sunk around it.

Dr Sardonicus 2018-04-06 13:25

[QUOTE=kladner;484447]Of course, extreme overuse of ground water is the real reason behind depleted aquifers. More that 30 years ago there were articles in Houston area papers about ground subsidence due to over-pumping. A photo provided to illustrate the problem showed a pump for a deep water well standing on its pipe 10 feet above the ground, which had sunk around it.[/QUOTE]
The same problem occurred in California during the recent years of drought. IIRC almond growers in particular experienced this sort of subsidence.

In the Great Plains, the enormous Ogalallah Aquifer has been greatly depleted. Aquifers are being used as "water mines." And when mines "play out," or simply become uneconomical, one result is "ghost towns." With water mines, the result could be a [i]lot[/i] of ghost towns.

ewmayer 2018-04-13 00:52

[url=www.realclimate.org/index.php/archives/2018/04/stronger-evidence-for-a-weaker-atlantic-overturning-circulation]Stronger evidence for a weaker Atlantic overturning circulation[/url] | RealClimate
[quote]In our study we conclude that the AMOC has weakened by about 15% since the middle of the 20th century.
...
[b]What effects could the slowdown have?
[/b]
It sounds paradoxical when one thinks of the shock-freeze scenario of the Hollywood film The Day After Tomorrow: a study by Duchez et al. (2016) shows that cold in the North Atlantic correlates with summer heat in Europe. This is due to the fact that the heat transport in the Atlantic has not yet decreased strongly enough to cause cooling also over the adjacent land areas – but the cold of the sea surface is sufficient to influence the air pressure distribution. It does that in such a way that an influx of warm air from the south into Europe is encouraged. In summer 2015, the subpolar Atlantic was colder than ever since records began in the 19th century – associated with a heat wave in Europe. Haarsma et al (2015) argue on the basis of model calculations that the weakening of the AMOC will be the main cause of changes in the summer circulation of the atmosphere over Europe in the future. Jackson et al (2015) found that the slowdown could lead to increased storm activity in Central Europe. And a number of studies suggest that if the AMOC weakens, sea levels on the US coast will rise more sharply (e.g. Yin et al. 2009). The impacts are currently being further researched, but a further AMOC slowdown cannot be considered good news.[/quote]

science_man_88 2018-04-13 01:12

15% decrease in flow means it takes about 17.7% longer to carry the same amount of heat etc. Assuming it's still strong enough to carry it.

kladner 2018-07-13 00:53

Orcas of the Pacific Northwest Are Starving and Disappearing
 
More ships, pollution, no salmon.
[URL]https://www.nytimes.com/2018/07/09/science/orcas-whales-endangered.html[/URL]
[QUOTE]SEATTLE — For the last three years, not one calf has been born to the dwindling pods of black-and-white killer whales spouting geysers of mist off the coast in the Pacific Northwest.

Normally four or five calves would be born each year among this fairly unique urban population of whales — pods named J, K and L. But most recently, the number of orcas here has dwindled to just 75, a 30-year-low in what seems to be an inexorable, perplexing decline.

Listed as endangered since 2005, the orcas are essentially starving, as their primary prey, the Chinook, or king salmon, are dying off. Just last month, another one of the Southern Resident killer whales — one nicknamed “Crewser” that hadn’t been seen since last November — [URL="https://www.whaleresearch.com/l92"]was presumed dead[/URL] by the Center for Whale Research.
[/QUOTE]

ewmayer 2018-10-10 22:01

[url=https://www.nakedcapitalism.com/2018/10/nobel-prizes-economics-awarded-withheld-climate-change-edition.html]Nobel Prizes in Economics, Awarded and Withheld (Climate Change Politics Edition)[/url] | naked capitalism
[quote]The reality is this is a nonprize for [Harvard’s Martin] Weitzman, an attempt to dismiss his approach to combating climate change, even though his position is far closer to the scientific mainstream than Nordhaus’. An example of the enlistment of the uncritical media in this enterprise is today’s New York Times, where Binyamin Appelbaum writes:
[i]
Mr. Nordhaus also was honored for his role in developing a model that allows economists to analyze the costs of climate change. His work undergirds a new United Nations report on the dangers of climate change, released Monday in South Korea.
[/i]
Wrong. The work Nordhaus pioneered in the social cost of carbon is mentioned only twice in the IPCC report, a box in Chapter 2 and another in Chapter 3. The reason it appears only in boxes is that, while the authors of the report wanted to include this work in the interest of being comprehensive, it plays no role in any of their substantive conclusions. And how could it? The report is about the dangers of even just 1.5º of warming, less than the conventional 2º target, and far less than the 3+º Nordhaus is comfortable with. Damages are expressed primarily in terms of uninhabitable land and climate refugees, agricultural failure and food security, and similarly nonmonetary outcomes, not the utility-from-consumption metric on which Nordhaus’ work rests.

The Nordhaus/Romer combo is so artificial and unconvincing it’s hard to avoid the impression that the prize not given to Weitzman is as important as the one given to Nordhaus. This is a clear political statement about how to deal with climate change and how not to deal with it. The Riksbank has spoken: it wants a gradual approach to carbon, one that makes as few economic demands as possible.[/quote]
Well, whaddya expect from a bunch of orthodox-economist central bankers who arrogated Nobel's name for their prize in order to lend it a prestige it does not deserve? Growth über Alles, baby!

Dr Sardonicus 2018-12-01 02:00

Things heat up in Australia...
 
Australian PM Scott Morrison said in the run up to planned protests about climate change, "We don't support our schools being turned into parliaments. What we want is more learning in schools and less activism in schools."

Resources Minister Matt Canavan had these words of wisdom for the protesting students, among other pearls:

"The best thing you learn about going to a protest is how to join the dole queue."

"I want kids to be at school to learn about how you build a mine, how you do geology, how you drill for oil and gas, which is one of the most remarkable scientific exploits of anywhere in the world that we do."

Apparently this did not go over well with the students. [url=https://www.abc.net.au/news/2018-11-30/australian-students-climate-change-protest-scott-morrison/10571168]Students strike for climate change protests, defying calls to stay in school[/url]

ewmayer 2018-12-01 04:26

[url=https://grist.org/article/we-broke-down-what-climate-change-will-do-region-by-region/]Breaking Down What Climate Change Will Do, [U.S.] Region by Region[/url] | Grist

tServo 2018-12-01 16:02

Climate change in 1 immensely depressing statistic
 
October 2018 was the 406th CONSECUTIVE month of above average global temperatures.

ewmayer 2019-01-24 03:31

[url=https://www.sciencedaily.com/releases/2019/01/190122104611.htm]We need to rethink everything we know about global warming[/url] | Science Daily
[quote]For a while now, the scientific community has known that global warming is caused by humanmade emissions in the form of greenhouse gases and global cooling by air pollution in the form of aerosols. However, new research published in Science by Hebrew University of Jerusalem Professor Daniel Rosenfeld shows that the degree to which aerosols cool the earth has been grossly underestimated, necessitating a recalculation of climate change models to more accurately predict the pace of global warming…. The fact that our planet is getting warmer even though aerosols are cooling it down at higher rates than previously thought brings us to a Catch-22 situation: Global efforts to improve air quality by developing cleaner fuels and burning less coal could end up harming our planet by reducing the number of aerosols in the atmosphere, and by doing so, diminishing aerosols’ cooling ability to offset global warming.[/quote]
A.k.a. "screwed if we do, screwed if we don't".


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