Why Extreme Rains Are Gaining Strength As The Climate Warms

[bluewave]

https://www.pik-potsdam.de/news/press-releases/record-wet-and-record-dry-months-increased-in-regions-worldwide-climate-change-drives-rainfall-extremes?set_language=en

Record-wet and record-dry months increased in regions worldwide: climate change drives rainfall extremes

 

12.12.2018 - More and more rainfall extremes are observed in regions around the globe – triggering both wet and dry records, a new study shows. Yet there are big differences between regions: The central and Eastern US, northern Europe and northern Asia have experienced heavy rainfall events that have led to severe floods in recent past. In contrast, most African regions have seen an increased frequency of months with a lack of rain. The study is the first to systematically analyze and quantify changes in record-breaking monthly rainfall events from all over the globe, based on data from roughly 50,000 weather stations worldwide. Climate change from fossil fuel greenhouse gases has long been expected to disturb rainfall patterns.

 

„We took a close look at observed monthly rainfall data - if it's not just a few days but several weeks that are record wet, this can accumulate over time and lead to large river floods, or to droughts if it is record dry,“ says lead author Jascha Lehman from the Potsdam Institute for Climate Impact Research (PIK). The impacts on people's livelihoods in the affected regions can be huge, ranging from flooded houses to endangered food security due to large-scale agricultural losses.

Downpour in parts of US, Europe, Russia – drought in parts of Africa

The US has so far seen an increase of record wet months by more than 25 percent in the Eastern and central parts over the period 1980-2013. Argentina and bordering countries have experienced an increase of 32 percent. In central and northern Europe the increase is between 19 and 37 percent. In the Asian part of Russia the increase is around 20 percent, while South East Asia shows an increase of about 10 percent.

The scientists ran strict tests for the statistical significance of observed changes. Therefore, they so far see significant changes in dry extremes just in Africa south of the Sahara and in the Sahel zone where dry records have increased by up to 50 percent. „This implies that approximately one out of three record-dry months in this regions would not have occurred without long-term climate change,“ says co-author Dim Coumou from the Institute for Environmental Studies (IVM) at Vrije Universiteit  Amsterdam. „A central conclusion from our study is that, generally, land regions in the tropics and sub-tropics have seen more dry records, and the northern mid- to high-latitudes more wet records – this largely fits the patterns that scientists expect from human-caused climate change.”

UN climate summit decides about future rainfall extremes 

The scientists compared observed wet and dry rainfall extremes to the number of extremes that would be expected in a climate without long-term changes. „We checked for new records – monthly rainfall values that have never been observed before in a given region since the beginning of systematic measurements more than a hundred years ago.“ Of course one expects to see some rainfall records simply due to natural variability. „Normally, record weather events occur by chance and we know how many would happen in a climate without warming,“ explains Jascha Lehmann. „It's like throwing a dice: on average, one out of six times you get a six. But by injecting huge amounts of greenhouse gases into the atmosphere, humankind has loaded the dice. In many regions, we throw sixes much more often with severe impacts for society and the environment.“

„It is worrying that we see significant increases of such extremes already at just one degree global warming,“ adds Lehmann. „Right now, governments from countries all over the world meet at the UN climate summit – if they do not agree on solutions to limit warming to well below 2 degrees, we're headed for 3-4 degrees within this century. Physics tells us that this would boost rainfall extremes even further.”

Article: Lehmann, J., Mempel, F., & Coumou, D. (2018): Increased occurrence of record-wet and record-dry months reflect changes in mean rainfall. Geophysical Research Letters, 45.
 

Weblink to the article, once it is published: https://doi.org/10.1029/2018GL079439 

 

[SENC]

On ‎11‎/‎21‎/‎2018 at 6:06 PM, bluewave said:

https://www.nature.com/articles/d41586-018-07447-1

NEWS FEATURE 

20 NOVEMBER 2018

Why extreme rains are gaining strength as the climate warms

 

From Atlantic hurricanes to the Indian monsoons, storms are getting worse and becoming more erratic.

 

The downpour began on 13 September, when the centre of Hurricane Florence was still hundreds of kilometres from North Carolina’s coast. As the giant storm lurched towards land, officials ordered more than 1.5 million people to evacuate, warning of “life-threatening” damage. On 15 September, Florence finally crashed into the United States, where it slowed to a crawl and unleashed even heavier rains. In some places, the deluge continued non-stop for four days.

By the time it was all over, Florence had dumped record amounts of rain — including nearly one metre in the town of Elizabethtown, North Carolina — and caused catastrophic flooding. Dozens of people died, and the storm racked up tens of billions of dollars in damages. Even now, months later, the area is struggling to recover.

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Respectfully.....

Full STOP..  The Article forgets "Floyd" of 1999.. (We got "massive flooding" then also..)

What this paper FAILS to mention is, N.C. (where the majority of flooding occurred) is basically one huge swamp.. Wetlands have been drained, filled or ditched.. By massive housing and development projects.. Lord, flooding happens when We get decent T-storms now, compared to 20-30 years ago.. Water in simple terms, has no-where to go..  WETLANDS used to "hold" and Filter the waters. So of course there's flooding,(now) IN Addition We were (on average)   when Florence occurred, above average on rainfall for the year.. (same as with Floyd). Water has nowhere to go.. BLAME over-development MORE than anything..

I've observed over the years, places that NEVER flooded before,  Do now. Take for example...

Here on the Beach, Part of the Island that is Carolina Beach, floods (almost) every high tide.. During High Lunar tides, It gets fairly bad, (and deep).. LOTS of Folks, Including those from UNCW AND Duke Uni, &  UNC-Chapel hill et al) are trying to state as FACT, this is "truly alarming" as AGW is causing this as seas are rising [/b]

Which is total BS! That part of the Island has ALWAYS flooded since I was 6 years Old & "Old Timers", Folks whom are 70~80 years old say the same thing, that part of the Island has ALWAYS been flooding problematically since They were kids also! though the "academia" states as "fact" it caused by "rising Sea levels", Which is pure un-mitigated BS..  

 

ALOT of AGW,  based on FALSE assumptions that MORE rainfall is happening due too..  AGW.. THAT is complete BS, On one hand ya'll are calling for droughts based on AGW, When it rains alil more, you blame it on AGW..

Which is it?

Look to the SKY, maybe, just maybe, Climate & Weather is based on.... Cough,, Cough,, the SUN? you  think? What If the Sun Dimmed (a lot) what would happen? WHAT IF Climate is based on the Solar Cycles? 11-200-400 year cycles AND "forcing" is contributing by (wait for it) Cosmic Rays..

As CO2 is a TRACE GAS. ALL of Ballyhoo, "based" on CO2 "causing" AGW is just that, Ballyhoo.. "cough" I mean Cow Flatulence.. YOU folks forget ONE BASIC thing about CO2, It makes PLANTS GROW bigger/faster and better.. Your "forgetting" something very basic taught in Biology class..  It's called Photosynthesis, FACT is MORE CO2 will be better for growing Crops/Trees so-forth and so-on.. FACT: Farmers (greenhouses) ADD CO2 to produce bigger better veggies, (and fruit), (Marijuana also) , growing FASTER, by introducing CO2 into the environment.. 

Guys think outside the box here..  Want to reduce CO2? Plant more trees!

 Reminds Me of the Same BS with the Ozone Layer/hole BS that happened during the 70's & 80's.. Once the international Law banning refrigerants was passed, it was like a light switch was turned off, Never heard a word about the "Ozone" Hole/Layer,after that.. If We didn't pass that Law BANNING those refrigerants,, WE WERE ALL GONNA DIE, by the year 2000! cause of getting irradiated to death.. Sheesh.. I wonder WHOM benefited from that? 

Again think outside the Box, give this video a watch.. Sorry for the Rant, Science IS NOT "settled", NO AMOUNT of money will solve AGW. (think about that for a minute), Maybe it's about taxing YOU, (all of US) … To what end?.. 

Again think outside the box, give this video a watch.. (seriously)..

 

 

 

[bdgwx]

11 hours ago, SENC said:

Look to the SKY, maybe, just maybe, Climate & Weather is based on.... Cough,, Cough,, the SUN? you  think? What If the Sun Dimmed (a lot) what would happen? WHAT IF Climate is based on the Solar Cycles? 11-200-400 year cycles AND "forcing" is contributing by (wait for it) Cosmic Rays..

The Sun is certainly one actor in modulating the climate, but it's not the only actor. Solar activity and total solar irradiance peaked around 1960 when it flat lined and then even began to decline in recent decades. From 1990 to present the Earth accumulated 250e21 joules of energy (most of which went into the ocean). This was during a period in which solar radiation declined. The fact is that the Sun can't the cause of the warming that is happening today.

Also, keep in mind that solar luminosity increases by about 1% every 100 million years. That means the Sun was 5% dimmer 500 million years ago when the Earth was much warmer. Clearly the Sun is not the only actor that determines Earth's equilibrium temperature through the paleoclimate record as well. There is a solution to the faint young Sun problem though. I bet you can guess what it is.

Regarding cosmic rays influence on the climate...this had already been pretty well rejected prior to the CERN experiments, but in 2016 CERN effectively put the last nail in the coffin.

http://science.sciencemag.org/content/354/6316/1119

Abstract: Fundamental questions remain about the origin of newly formed atmospheric aerosol particles because data from laboratory measurements have been insufficient to build global models. In contrast, gas-phase chemistry models have been based on laboratory kinetics measurements for decades. We built a global model of aerosol formation by using extensive laboratory measurements of rates of nucleation involving sulfuric acid, ammonia, ions, and organic compounds conducted in the CERN CLOUD (Cosmics Leaving Outdoor Droplets) chamber. The simulations and a comparison with atmospheric observations show that nearly all nucleation throughout the present-day atmosphere involves ammonia or biogenic organic compounds, in addition to sulfuric acid. A considerable fraction of nucleation involves ions, but the relatively weak dependence on ion concentrations indicates that for the processes studied, variations in cosmic ray intensity do not appreciably affect climate through nucleation in the present-day atmosphere.

Also worth reading are Muscheler 2005, Lockwood 2007, Sloan 2008, Pierce 2009, Overholt 2009, Kulmala 2010, Calogovic 2010, and Erlykin 2013 which all say that GCRs have little if any effect on the climate. 

11 hours ago, SENC said:

As CO2 is a TRACE GAS. ALL of Ballyhoo, "based" on CO2 "causing" AGW is just that, Ballyhoo.. "cough" I mean Cow Flatulence..

Mt Tambora ejected 60 Mt of SO2. This sulfur dioxide aerosol cloud spread around the entire Earth causing the year without a summer in 1816. This cooled the plant by about 0.6C globally with some estimates being as high as 1.0C globally and 3.0C in the NH. 60 Mt is equivalent to 0.012 ppm by mass. So a 0.012 ppm increase in SO2 can cause 0.6C of cooling but a 120 ppm increase in CO2 does nothing? Also, CFCs of which some species are measured in ppt (parts per trillion) are very destructive to stratospheric ozone.

Anyway, the ability of trace gases like CO2 and CH4 to cause warming are well grounded in molecular physics and quantum mechanics principals and have been demonstrated as far back as the 1860's and even quantified as far back as the 1890's.

Oh, and cow flatulence is actually CH4. CH4 happens to be a greenhouse gas as well that produces a positive radiative forcing on the climate system too.

11 hours ago, SENC said:

YOU folks forget ONE BASIC thing about CO2, It makes PLANTS GROW bigger/faster and better.. Your "forgetting" something very basic taught in Biology class..  It's called Photosynthesis, FACT is MORE CO2 will be better for growing Crops/Trees so-forth and so-on.. FACT: Farmers (greenhouses) ADD CO2 to produce bigger better veggies, (and fruit), (Marijuana also) , growing FASTER, by introducing CO2 into the environment.. 

True. Vegetation in general thrives on CO2 because it is an essential ingredient for photosynthesis. However, just like CO2 isn't the only the thing that modulates the climate it isn't the only thing that modulates vegetation growth either. You have to consider soil chemistry, sunlight, moisture, temperature, surrounding biological activity, etc as well. CO2 warms the planet and as a result the climate will change in different ways for different regions. These climate changes may offset the biological benefit of higher CO2. Also, keep in mind that not all vegetation thrives equally on higher CO2 concentrations. It is believed that C4 plants evolved specifically as a way of coping with lower CO2 concentrations, moisture, and temperature. Corn is an example of a C4 crop that may not benefit much if at all by higher CO2 concentrations, but could be impacted negatively by climate change.

11 hours ago, SENC said:

Reminds Me of the Same BS with the Ozone Layer/hole BS that happened during the 70's & 80's.. Once the international Law banning refrigerants was passed, it was like a light switch was turned off, Never heard a word about the "Ozone" Hole/Layer,after that.. If We didn't pass that Law BANNING those refrigerants,, WE WERE ALL GONNA DIE, by the year 2000! cause of getting irradiated to death.. Sheesh.. I wonder WHOM benefited from that? 

CFCs really do deplete ozone. The science is pretty solid here too.