Claim: More Frequent Less Intense Rainfall is Now a Problem

Map of the Gila River watershed-drainage basin — located in New Mexico and Arizona.

Map of the Gila River watershed-drainage basin — located in New Mexico and Arizona. By Kmusser (Self-made, based on USGS data.) [CC BY-SA 2.5], via Wikimedia Commons

Guest essay by Eric Worrall

Lecturer in Physical Geography Michael Singer has noticed that climate hasn’t brought greater precipitation, as Trenberth predicted it would – but he still worries about the impact of climate change on watersheds.

How understanding regional rainstorms will help the world manage climate change

December 8, 2017 2.03am AEDT

Michael Singer

Lecturer in Physical Geography (Hydrology and Geomorphology), Cardiff University

There is a theory in physics that tells us that a warmer atmosphere can hold more moisture (~7% more per 1°C increase), so we might expect that places with increasing temperatures will experience more water evaporation from the land, and also experience heavier rainfall. But we don’t have great evidence of more intense rainfall for many places across the world, even though the upward temperature trends are compelling for much of the globe.

It is actually very difficult to observe trends in rainfall, because we often rely on data and model outputs that are at the wrong scales. Global rainfall datasets and output from climate models are typically resolved on timescales of days or months and at spatial scales larger than most river basins.

In general, scientists have had a poor understanding of how a warming climate will affect the magnitude, timing, and spatial patterns of rainfall. Yet these aspects of the climate system are fundamental to assess the sustainability of water resources and even flood risks, especially in drier parts of the globe.

Several years ago, I came across a rich dataset on rainstorms for a place called Walnut Gulch, a watershed – an area of land that separates waters flowing into different rivers – near the city of Tombstone in south-eastern Arizona. The US Department of Agriculture has been collecting detailed information about every single storm that occurred from 1954 until the present day at 85 separate gauging locations. We already knew temperatures had been rising here, increasing by ~2°C in a matter of decades. And this trove of rainfall data enabled us to examine whether there were trends in rainstorms that corresponded to the rising temperatures.

Map of the Gila River watershed-drainage basin — located in New Mexico and Arizona.

Map of the Gila River watershed-drainage basin — located in New Mexico and Arizona. By Kmusser (Self-made, based on USGS data.) [CC BY-SA 2.5], via Wikimedia Commons

We were surprised to find that even while total rainfall slightly increased over this period and more rainstorms occurred over time, each storm was less intense and lasted longer. This means that less rainwater has run off the landscape into rivers since the 1950s, so more of the water from the sky has returned to the atmosphere and less of it contributed to regional water resources.

In other words, the theory which predicts heavier (more intense) rainfall due to warming does not hold for this region. We believe it breaks down here and in other dry environments because there is not enough moisture in the landscape to evaporate and satisfy the higher demand of the atmosphere. Our findings also suggest that water resources in this desert region may become increasingly strained due to changes in the regional climate.

The rainfall study quoted by Michael Singer is a 2011 Trenberth study;

Changes in precipitation with climate change

Kevin E. Trenberth*

National Center for Atmospheric Research, Box 3000, Boulder, Colorado 80307, USA


ABSTRACT: There is a direct influence of global warming on precipitation. Increased heating leads to greater evaporation and thus surface drying, thereby increasing the intensity and duration of drought. However, the water holding capacity of air increases by about 7% per 1°C warming, which leads to increased water vapor in the atmosphere. Hence, storms, whether individual thunderstorms, extratropical rain or snow storms, or tropical cyclones, supplied with increased moisture, produce more intense precipitation events. Such events are observed to be widely occurring, even where total precipitation is decreasing: ‘it never rains but it pours!’ This increases the risk of flooding. The atmospheric and surface energy budget plays a critical role in the hydrological cycle, and also in the slower rate of change that occurs in total precipitation than total column water vapor. With modest changes in winds, patterns of precipitation do not change much, but result in dry areas becoming drier (generally throughout the subtropics) and wet areas becoming wetter, especially in the mid- to high latitudes: the ‘rich get richer and the poor get poorer’. This pattern is simulated by climate models and is projected to continue into the future. Because, with warming, more precipitation occurs as rain instead of snow and snow melts earlier, there is increased runoff and risk of flooding in early spring, but increased risk of drought in summer, especially over continental areas. However, with more precipitation per unit of upward motion in the atmosphere, i.e. ‘more bang for the buck’, atmospheric circulation weakens, causing monsoons to falter. In the tropics and subtropics, precipitation patterns are dominated by shifts as sea surface temperatures change, with El Niño a good example. The volcanic eruption of Mount Pinatubo in 1991 led to an unprecedented drop in land precipitation and runoff, and to widespread drought, as precipitation shifted from land to oceans and evaporation faltered, providing lessons for possible geoengineering. Most models simulate precipitation that occurs prematurely and too often, and with insufficient intensity, resulting in recycling that is too large and a lifetime of moisture in the atmosphere that is too short, which affects runoff and soil moisture.

Read more:

Michael Singer worries that less intense but more frequent rain will reduce available runoff. But the effect of more frequent rainfall on arid regions in a lot of cases is likely to be profound. Intense one off rain events mostly drain away – parched soil often can’t absorb water until it has been soaked repeatedly by rain. But more frequent longer lasting rainfall, in many regions, should make it possible for grasslands and even trees to establish in formerly extremely arid regions. Vegetation tends to establish and protect its own soil moisture – providing there is some moisture available to protect.


newest oldest most voted
Notify of

“It is actually very difficult to observe trends in rainfall..”

…well yeah, when you start off with this

“even though the upward temperature trends are compelling for much of the globe.”

….what happened to the pause/hiatus?

These morons are all over the place……no wonder

Their timeframe is “since 1954” (i.e., about sixty years). Over that time period I would not dispute their claim that there’s been an upward temperature trend:


Since 1940, might be a different matter

And please, no HadCrud graphs…. unreliable for the 1940’s due to agenda driven data changes.


true….still annoys me though…they might have good news, and it’s still bad news

Actually, in that area, there has been NO trend. Unless it shot up in the last six years, which I truly doubt.

I took the data from the Tombstone station in 2011 for an exercise in college statistics (which kicked me over to the climate skeptic side). It shows absolutely NO trend from 1880 to 2011, unless you do a fourth order curve fit – and that shows a very slight DOWN trend (although not significant at all).

That was a very good station to use. It was in town, in the same place since 1880, so was read regularly – but the town is just about all wood buildings and dirt streets, for the tourists. Hardly any UHI at all.

Surprise, the station is now gone, as are its records on the web – the “official” records at the closest station are now all from Sierra Vista – which has seen extreme urbanization since about 1995. Now, THAT station has approximately a 1.8C rise showing.

So, for that particular area – bogus data. Rain, I don’t know, I haven’t looked. But the majority of the rain in this part of the country depends not on evaporation from land, but from the Gulf of Mexico – and the jet stream, for how much moisture actually comes up during the monsoon season.

Gary Pearse

Andy, interestingly they accept that the 30s-mid 40s in the US was pretty warm but US only is, what, 3%of the globe. Well Canada, Greenland,Scandinavia, Europe, Siberia added on are, what, 30% (the distance from Moscow to Vladivostok is the same distance as Moscow to Chicago!). But then I learned the Capetown, South Africa long term raw temperature chart looks just like the US one before fudging and then the Paraguay historical raw temperatures ditto, we can add on two more continents! Here is Capetown’s:
comment image

Gary Pearse

Andy, my response to you wound up somewhere else (near the bottom):

Gary Pearse
December 9, 2017 at 4:19 pm

Gary Pearse

Here’s Capetown, South Africa’s raw temperature chart (also Canada, Greenland, Scandinavia, Europe, Siberia, Paraguay are the same). These corroborate the raw US temperatures giving them status:

comment image

Gary Pearse

Oops mods, screwed up.

“Capetown, South Africa long term raw temperature chart looks just like the US one before fudging”
Capetown needs adjustment. There was a station move from Observatory to the airport in 1961, which us responsible for the dip. But the Observatory continued on, with a diffrent station number. Here (from here) is a plot of the GHCN Cape Town record (in red) with GHCN adjusted (in green), and the continuing Observatory record inblue. Continued warming.
comment image

Clive Bond

Australian temperatures were higher in the 1930s until the Bureau of Meteorology “homogenized” them down.


“Capetown needs adjustment”

Of course it does, Nick..

Doesn’t meet regional expectations ???

And we all know exactly which way that “adjustment™” would HAVE to be.
comment image

old white guy

managing that which is unmanageable. yep.

“Doesn’t meet regional expectations ???”
Nothing to do with regional expectations. We know the station moved, and when. And we know what the temperatures would have been without the move, because they were still measured in the old location. The blue curve in the graph. The “adjusted” curve is just the actually observed measures in a single location.


Adjusting for that 1961 move seems to have had a dramatic effect on the 19th century trend.


Seriously Nick, almost 1/2 degree of cooling is adjusted to 1/2 degree of warming in the first 40 years of your graph. That accounts for a lot of the overall warming claimed. UHI probably accounts for the rest – just imagine the changes Capetown has seen in the last 150+ years.

“Surprise, the station is now gone, as are its records on the web”
Tombstone, AZ, has not dosappeared from the web. It is a station in GHCN V3, used by all indices. The data sheet page is here. The unadjusted data shows a strong uptrend.

“Seriously Nick, almost 1/2 degree of cooling is adjusted to 1/2 degree of warming “
Hard to see ½° of cooling. But the Cape Town data was claimed to show no warming. And, unadjusted for the Observatory site, it shows plenty. The early adjustment probably allows for the pre-Stevenson screen period.


“Hard to see ½° of cooling.”

Just eyeballing it, but either way, there’s more than a full degree of cooling the past in the adjustments. That’s bigger than the adjustment for the station move, as shown in these charts you posted here in January.
comment image

Writing Observer:

Tombstone station…shows absolutely NO trend from 1880 to 2011…the station is now gone…

The Tombstone station is still reporting, as it apparently has since 1893 (not 1880):

Rather spotty record. When you exclude years with more than 14 days of missing data you see trends of increasing temperature and declining precipitation.

Extreme Hiatus

But the hiatus, like all things caused by CAGW, is extreme. That’s why everything is still so “weird” and unprecedented and worse than we thought.

Extreme Hiatus

Forgot to note, my comment was in response to Latitude’s “….what happened to the pause/hiatus?”

Robert W Turner

I agree.

This means that less rainwater has run off the landscape into rivers since the 1950s, so more of the water from the sky has returned to the atmosphere and less of it contributed to regional water resources.

…We believe it breaks down here and in other dry environments because there is not enough moisture in the landscape to evaporate and satisfy the higher demand of the atmosphere.

They jump from less measured runoff, to less water in the environment. The exact opposite happens, if less water runs off and more is allowed to soak in the soil, there is more water in the environment.
And it appears the region is actually gaining vegetation.

Then they take that sophistry and make a belief out of it, which they then use to “make a finding.”

Our findings also suggest that water resources in this desert region may become increasingly strained due to changes in the regional climate.

It’s the complete opposite of empirical observations from deserts around the planet.

george e. smith

So the California Oroville dam spillway disaster was caused by not enough rain ??

Got it ! I just knew there had to be a simple explanation.



No, but on the belief of less rain!


That might also explain why fires are out of control in California–they anticipated less rain, hence less vegetation, and certainly less fires.

The exact opposite appears to have happened–more rain on the land, which caused more vegetation to grow, and that produced more fuel for the fires.

Homes are destroyed and the overall loss is staggering!

Stupid conclusions that conform to a pre-determined theology can have serious and demonstrable consequences!


I prefer my porridge just so. Anything else is global warming.


Roseanne Rosannadanna (Gilda Radner in early Saturday Night Live skits): “It’s like my daddy always said to me. ‘You know, Roseanne Rosannadanna, it’s always somethin'”

Somebody’s always saying we are “supposed” to have this mythical Goldilocks climate – – not too hot, not too cold, but always just right.

But Mother Nature never read Goldilocks

CHANGE is the only constant

NW sage

Agree with these comments – Are we supposed to be alarmed if there is ANY change, AT ALL? I suppose we are to assume the only GOOD weather (clouds, wind, rain, whatever…) is CONSTANT, UNCHANGING weather! Anything else is BAD, and the earth and its occupants will be unable to survive it?

Longer, less-intense rainfall events would increase absorption of water by the soil, replenish groundwater, and reduce erosion, compared to the opposite trend. What’s not to like about that??

Its not scary.

Gunga din

It might let food grow in the desert.

It appears he doesn’t even consider absorption by the soil …

We were surprised to find that even while total rainfall slightly increased over this period and more rainstorms occurred over time, each storm was less intense and lasted longer. This means that less rainwater has run off the landscape into rivers since the 1950s, so more of the water from the sky has returned to the atmosphere and less of it contributed to regional water resources.

Mmmm … has he not heard of “wells” and the “water table” and the like?


He also doesn’t know how deserts work. Not only is groundwater crucial (think oasis), desert plants like cacti need to soak up and store that water in their tissues. They lost leaves and have waxy exterior photosynthetic surfaces except for their stomata to absolutely minimize evapotranspiration. The cactus spines are protection against animal predators who would otherwise eat cacti for the water content. In fact in west Texas droughts, one trick is to burn off the spines and let cattle munch on the remaining prickly pear pads as a water source.


My thoughts exactly.
I am pretty sure it is considered less beneficial when rain falls hard and fast, particularly on hard dry ground.
What is being described here should also reduce the frequency and severity of flash floods, which kill people every year.
It seems to be literally true that nothing is good news to a “climate scientist”.

“It appears he doesn’t even consider absorption by the soil “
No, that is exactly what he is talking about. It’s standard catchment hydrology. Heavy rain makes a lot of surface runoff which goes into streams. Prolonged rain infiltrates more into the soil, where most of it returns to the air via evapotranspiration. Some gets into streams via water table flow, but that is just a fraction.

Nick, you miss the point. Desert ecology DOES NOT rely on runoff into rivers. It relies on groundwater, whichnrelies on percolation into hot dry baked soil. At least those deserts in Arizona, with which I have more than a passing familiarity. Had a significant Arizona native cactus collection in the sunroom at one point. Even started saguaro cacti from seed and grew them to about 6 inches in two years as giveaways under supplemental grow lighting since sunroom was in Chicago, not Phoenix. And trust me, despite flash floods and impoundment dams on the Salt River, Phoenix and environs would not exist except for the Colorado compact, Lake Powell behind Glen Canyon dam and lake Mead behind Hoover dam, and the Rocky Mountain seasonal snow melt feeding both—which has about zero to do with Hadley cell circulation. This paper shows a fundamental ignorance of regional SW US hydrology. See also the water chapter of my ebook Gaia’s Limits for pictures and more details.

Robert W Turner

Does Nick actually think that streamflow and the amount of water in man made reservoirs dictates regional precipitation?

“Nick, you miss the point. Desert ecology DOES NOT rely on runoff into rivers.”
I didn’t say it did. There is nothing about that in the quote highlighted by Willis. It is just about where rainwater goes, and as they say, it’s heavy rain that fills the rivers and dams. Sustained rain makes more water available to plants, which return it to the air.

“This paper shows a fundamental ignorance of regional SW US hydrology.”
It isn’t a paper, it is an article in the Conversation. The author is a hydrologist who grew up in SW USA. I think he knows what he is talking about.


he grew up there, ergo he knows what he is talking about?
Excuse me, but that sounds like a spectacularly unscientific way to determine veracity.
How about we just stick to what he writes, and weigh that on the merits of the argument?

“he grew up there, ergo he knows what he is talking about”
And Rud grows cactus. OK, so where do you think he displays ignorance?

Also my thoughts. A greater proportion of heavy rain runs off, so more evenly spread rainfall will contribute more to aquifers / water tables.


“OK, so where do you think he displays ignorance?”
Well, first let me say that personally, I am not going to use my extensive experience in growing xerophytic plants, nor my current collection of many dozens of species of cacti, of yucca, of agaves, or of succulents, as evidence that I know what I am talking about.
Or even the fact of having visited this area and camped out there, and seen the rains for myself.
Simply the evidence, and the illogic of his conclusions.
There is no good reason to think he is doing anything more that taking a WAG, and then using poor reasoning to arrive at a speculative conclusion.


There are a lot of reasons to be dubious of a persons birthplace, or even their professional credentials, as any sort of evidence that they are correct in all of their pronouncements and ideas.
We all know that those things are completely irrelevant in a scientific frame of reference.
As proof of this assertion, I can point you a whole bunch of people who are from NYC, including a bunch of professional engineers, who are 100% sure that the Twin Towers could not have collapsed from being hit by planes and having fires burn for the short time that it took for the buildings to collapse.


Exactly. Common sense.


Yep, and the more of the soaking into the ground = less running into the sea = less sea level rise = the more the glaciers can melt, to take up the slack.
Sounds ok to me.

“climate hasn’t brought greater precipitation, as Trenberth predicted it would”
Trenberth pointed out that in general warmer atmospheres can hold more water. But he wasn’t predicting more rain in Arizona. From that quote:

” With modest changes in winds, patterns of precipitation do not change much, but result in dry areas becoming drier (generally throughout the subtropics) and wet areas becoming wetter, especially in the mid- to high latitudes: the ‘rich get richer and the poor get poorer’. This pattern is simulated by climate models and is projected to continue into the future.”

Arizona is a classic dry area in the subtropics. In fact, it has long been expected that a belt of landaround 30-35° which relies on W winds for rain will get drier. That is because the Hadley cells, which produce the band of westerly winds around 40° will expand, and move this wind pattern further North.


Perhaps, but Arizona also gets significant rain during their annual monsoon, when winds reverse and come from the southeast and south.


True. PHX is actually just fractionally above the traditional desert level of precip, ie 8″.

Average annual precipitation – rainfall: 8.04 inch
Days per year with precipitation – rainfall: 36 days

Bengt Abelsson

Well, Trenberth predicts dry areas to become drier. Singer shows that reality in Arizona is more rain.
Confidence in climate models increase? Adjust Arizona to be a rainforest type of landscape?

“Singer shows that reality in Arizona is more rain.”
He’s talking about a specific dataset from Walnut Gulch. He says:
“We were surprised to find that even while total rainfall slightly increased over this period…”

Don K

It’s probably more complex than that Nick. While Southern Arizona gets frontal storms in the Winter some years, it also gets often violent Summer thunderstorms most years supported by inflows of humid air from the Gulfs of Mexico and California. I’m a bit skeptical that either the frontal storms or the Southwest Monsoon is much influenced by local temperatures in the very arid region. More likely the opposite I should think. On top of which the terrain is anything but flat. Tombstone is at 1383 meters. But the mountains in to the South near Sierra Vista top 2800 meters. They likely have a rain shadow that may affect Tombstone at times.

But, yes, a Northward shift in weather patterns would be a problem for the ever growing population in the US SouthWest. I’m skeptical there is sufficient fresh water averaged over the long run even today to fully support the population AND industry, AND agriculture. The dendrochronology folks tell us there have been numerous multidecade droughts in the region in the past. It’s not entirely clear that those dry spells are linked to temperature, but it’s not clear that they aren’t.

Canada OTOH would likely be a big winner. Second largest nation on the planet and hardly anyone lives there because it’s simply too freaking cold.

Don K
“It’s probably more complex than that Nick”
Yes. It probably depends how far west. We have a similar thing in Australia. SW Australia, a big wheat region around 32-36°S, is getting drier. N Australia is getting wetter from the monsoons, which are extending further south. Somewhere in between breaks even.

Doc Chuck

Here is some of that complexity from a former Arizonan. Phoenix and north ordinarily receives it greatest precipitation in January from the southernmost tails of weather fronts crossing America’s west coast out of the Gulf of Alaska; while Tucson’s wettest month is usually August from monsoonal atmospheric water vapor coming north from the Gulf of California (Sea of Cortez). But while local atmospheric water vapor is an essential ingredient, it must be cooled in order to condense and precipitate. Phoenix’s winter rains occur as a leading moist warm front is overtaken by a cold front; but Tucson’s summer downpours follow the cooling convection of warm ground-heated water vapor laden air up into towering cumulus thunderheads that often also sport lightning.
Now when a multi-decadal “climatic” drift in temperature is referred to, I take it that these are daily averages of both highs and lows. Small problem: If these consist of actually little changed daily highs combined with significantly less cool nighttime lows in those consequently elevated averages, why do we imagine we are thus witnessing desperately soaring trends in baking daytime heat?
Seems to me that over my reasonably long lifetime what lately often passes for “science”, at least as widely portrayed to the public, has been transformed from the reporting of carefully recorded detailed observations into some facile narrative that suits a post-modern lack of care for teasing out resident truths (and lacking the humility to say “actually nobody knows a lot about that yet” but it’s interesting, isn’t it?) in favor of leaving self-aggrandizing impressions of mastery of a field well beyond the solid evidence. Have we become dumb as rocks about all this, or is this actually “anything to make a difference” for the CAUSE that justifies our existence before we drop? America wants to know.


“That is because the Hadley cells, which produce the band of westerly winds around 40° will expand, and move this wind pattern further North.”

It so happens that Arizona gets most of its rain from the summer monsoon which is on the southern side of the Hadley Cell. August is the wettest (=least dry) month in Phoenix.

“August is the wettest (=least dry) month in Phoenix.”
Just. The weather data is here. 110 of the annual 204 mm fall Nov-March.


It may be a totally different story in other areas nearby.
In Summer, there are thunderstorms over the mountains around there nearly every afternoon.

Michael Jankowski

So let’s summarize…

-Trenberth doesn’t say AZ will get wetter or have more intense storm events
-Singer is a hydrologist and knows what he’s talking about but is surprised to find this part of AZ has gotten wetter (as opposed to what Trenberth claims should happen) and has less intense storm events (apparently showing a poor understanding of what Trenberth claims should happen)
-even though Singer/data and Trenberth come to opposite conclusions for this study area, they agree
-if you still see that Trenberth and Singer/data disagree, then you have to realize that this study area is a tiny one and simply an exception
-hydrologists are not climate scientists, even though Singer claims one of his research subjects is climate change, one of his areas of expertise is climate, climate impacts on hydrology are well-covered by the IPCC, and hydrology has an immense impact on climate


Modern climate science, and those that purport to practice it ( and whom apparently needs lots more practice), is not given to being tied down by any need for consistency or even sticking to one story for long…except for two items: CO2 is bad, and all change is our fault and catastrophically horrible.

John Bell

It is always what ever is worse for the area, more rain, less rain, hotter, colder, more snow, less snow, they have morbid imaginations.


The banal conclusion is that every change happensand all change is bad in the mind of climate conservatives which traditionally are called ‘progressives’ even when they’re not.

Curious George

Progressives oppose any change other than the one they fight for.

michael hart

And the change they oppose the most is changing their minds, at least for the better. It is always worse.


Angel Gabriel: “Good news, Debbie. The earth has been restored to perfection and you can live in everlasting joy.”
Debbie Downer, the Carbon Sinner: “We’re really going to have to pay for all of this happiness someday.”


Sad Trombone: “Wah wah”

Nigel S

My mother told me that in her youth in Yorkshire the standard response to “what a beautiful day!” was “we shall pay for it later!”. A mindset brilliantly captured by Monty Python.


Before the coming of the Great Satan, humanity, earth was static and unchanging. Therefore every change is bad, because Earth was perfect before.

I’m looking forward to reading how terrible for earth’s myriad ecosystems that topical cyclones have declined in number. And intensity.


Well, technically, from a Biblical viewpoint, that is correct. Until Satan showed up, we were in the Garden of Eden. Oh, wait, you meant “the Great Satan” as in human beings…….


If its from “climate models”

The chances of this “prediction” being correct are less than the toss of a coin.

Eric Simpson

More frequent less intense rain is a problem.

And so is less frequent more intense rainfall. And drought. And abnormally extended periods of just totally normal amounts of rain. A joke.
comment image


A poor mans Tim Flannery.

Pat McAdoo


And we need to campaign to get back to using “global warming” versus all the climate stuff.

I see nothing wrong with this group of posters using anecdotal data from real world gardening/ranching/fishing/hunting experiences gathered over a half a century or more. After all, it was observed phenomena and not produced by a model. Granted, the sample size is small, and there may be biases as we see from the warmists, but what the hell.


Bruce Cobb

No matter what happens, we’re doomed. Because climate change.


Want to get published? Just mention Climate Change in whatever you’re writing.


Obviously Michael Singer doesn’t live in Melbourne.

These articles are straying far too deep into the weeds. What does understanding regional rainstorms have to do with the price of tea in China? It has about the same merit as studying butterflies in Brazil to predict tornadoes in Texas and counting the number of polar bears dancing on ice floes. Focus on the understanding the basics. Can a chaotic event be predicted? All the other nonsense is noise. Working in the noise window is a waste of time and money.

Recently in southern Australia, there have been less frequent more Intense rainfalls which have not been an unusual problem, so I guess it depends on where you are at the time, as to what you think of it all.

That woild be taken by warmunists as corroborating evidence, because Australia is down under and everything should therefore be upside down.


Soɯǝɥoʍ ʇɥɐʇ poǝsu,ʇ sonup ɹᴉƃɥʇ qnʇ ʎon pᴉp sɐʎ ʍɐɹɯnuᴉsʇs˙˙˙

Stephen Skinner

“There is a theory in physics that tells us that a warmer atmosphere can hold more moisture (~7% more per 1°C increase), so we might expect that places with increasing temperatures will experience more water evaporation from the land, and also experience heavier rainfall.”
I thought this was why the Sahara was green some 8,000 years ago, because the world was warmer than now. And being greener and wetter with moisture to evaporate would mean local temperatures would be lower. Is that not so?

Extreme Hiatus

“Claim: More Frequent Less Intense Rainfall is Now a Problem”

Wow, these new ‘scientific discoveries’ are becoming increasingly ridiculous. So now we have the more or less frequent and more or less intense rainfall theory of CAGW impacts. That pretty much covers everything.

I look forward to the ‘discovery’ that The Warming makes rain more wet, or less wet, or both.

F. Leghorn

Are these people intentionally trying to out-stupid each other? Because they are succeeding in spectacular fashion.

To be accepted into the academic warmunist priesthood, you have to have scary research findings. All the low hanging fruit was picked long ago, stuff like more extremes, accelerating sea level rise, polar bears. So now the wanna be’s are into even more absurd second and third order stuff like this. For another example, see my Totten Glacier post over at Climate Etc. Or essays Last Cup of Coffee and Greenhouse Effects in ebook Blowing Smoke.

Extreme Hiatus

I thought this one about The Warming causing Australian lizards to become more stupid was pretty good. Now we have an exciting new threat called “mental dimming,” as reported in the ‘prestigious’ National Geographic:

“Reptiles were already facing steep odds from climate change—it’s estimated that one-fifth of all lizard species could be extinct by 2080. Mental dimming could further stack the deck.”

This may apply more to CAGW ‘scientists.’

EH, yup, you spotted another great example in the mental dimming of bearded lizards paper. Talk about shoddy science. I recall JoNova shredded that one pretty thoroughly, now that you mention it.

Don K

“Reptiles were already facing steep odds from climate change—it’s estimated that one-fifth of all lizard species could be extinct by 2080. Mental dimming could further stack the deck.”

Well, it is true that something caused some problems for reptiles in the Cretaceous — which is believed to have been pretty warm, Of course, it took 80 million years to kill them off and snakes and lizards were among the survivors of the K-T extinction event. So maybe Australia’s lizards have some hope of lasting beyond 2080.

(BTW, how does one distinguish a stupid lizard from a smart lizard?)

DK, with great difficulty. Hence the seminal significance of this ‘finding’.

Extreme Hiatus

“(BTW, how does one distinguish a stupid lizard from a smart lizard?)”

Excellent point Don K. Given how potentially catastrophic this may be there’s clearly an urgent need for massive funding to research this emerging problem. And since The Warming is the obvious cause, there should be plenty of cash available for this.

I am actually a bit confused by this disturbing news. In my experience with lizards and other reptiles I have found them to appear more stupid when its colder. Indeed, on a very cold day they often just sit there, motionless, with a vacant stare, even when approached. They appear to be morons. But then, as they say, ‘still waters run deep’ and they may simply be pondering the meaning of the universe or something.

John F. Hultquist

Don K @ 3:43,

Just this week I read that the K-T Boundary is now called the Cretaceous–Paleogene boundary.
LINK to wikipedia

…and elsewhere:
The Tertiary is no longer recognized as a formal unit by the International Commission on Stratigraphy, but the word is still widely used. The traditional span of the Tertiary has been divided between the Paleogene and …

I can’t keep up with this stuff. My old texts have to go.


Arizona is familiar with jokesters like Singer.comment image
– Boothill Graveyard,
Tombstone, Arizona

Hysterically funny tombstone from Tombstone. Dunno if real or fake.
I just gave my two Army/Navy replica black powder civil war Colt .44 revolvers to my brothers middle son. A present rewarding his newly minted PhD in mathematics on a subject in topology that I definitely and totally do not understand after a two hour dissertation discussion at this years just past farm deer hunt. Kit Complete with bullet moulds, powder flasks, cappers, nipple wrenches and extra nipples, and a loading stand, all in a presentation box. Had to spend half a day teaching the young mathematician how to load and fire those things in my farm quarry rifle range. He was thrilled—and surprised how accurate they were. (No Les, No More). I educated yet another of the next generation in ways of the past. He had previously learned at my farm the utility of a peavy in making firewood from logs using chain saws and splitting axes. He has yet to learn how to run the diesel tractor and logging chains that brought the logs to the firewood production spot by the cabin.

Nigel S

V. good, every man should know how to build his own house (and defend it too I guess as my American son-in-law reminds me).


I inherited my great-grandfather’s Remington Model 1858 (so-called) revolver in .36 cal Navy.

Have never fired it, but believe it would hold up. A very durable pistol.


The full original inscription reads:
“Here lies the body of Lester Moore
Shot to death with a .44,
No less, no more.”


Don’t they mean “No Less; no Moore”?

“Lecturer in Physical Geography Michael Singer has noticed that climate hasn’t brought greater precipitation, as Trenberth predicted it would.”

As a Lukewarmer I’d expect there would have to be more precipitation if there were global warming. So if there is no moreprecipiatation I can only think of 2 possibilities 1) It’s not being measured correctly or 2) It hasn’t warmed and the temperature record is wrong (or manipulated into insanity).

Nigel S

The quality of mercy is not strained;
It droppeth as the gentle rain from heaven
Upon the place beneath. It is twice blest;
It blesseth him that gives and him that takes:

‘Under the rocks, and stones there is water underground’

Dave in Canmore

Nigel thanks for the Talking Heads ref. Gonna have that in my head all night now. (that’s a good thing 🙂


We know how warmer climate affects rainfall, because of the Holocene Climatic Optimum, which was at least 2 degrees C warmer than now globally. Probably more.

The good news is that it was better then than now for humans and other living things. Also during the previous interglacial, the Eemian, which was even balmier.

Mike Maguire

Greatest observed point precipitation values for the USA. Interesting that all these extreme records below were set prior to 1983:

However, heavy downpours have increased, especially in the Midwest and Northeast US:

As an operational meteorologist, I have observed a noteworthy increase in high end rain events in the Midwest over the past 35 years. As evidence, I did a comprehensive study to use in an insurance claim(that resulted in a $15,000 settlement in my favor) for the Paducah Kentucky area of responsibility. The data below is for Evansville IN, going back to 1897. This is where I live:

Evansville IN Spring March-May

Top 10 Wettest
Rank     Precipitation (inches)     Year
1     25.48     2008-wettest ever for any season
2     25.01     2011-2nd wettest ever for any season
3     24.34     1996
4     23.46     1983
5     22.42     1927
6     22.10     1935
7     21.63     1995
8     21.45     1961
9     20.48     2002
10   19.74     1897

*6 of the top 10 wettest occurred since 1981
*The top 4 wettest since 1981
*The 2 wettest Springs since 1897 were in the past 10 years and these were also the 2 wettest seasons ever.

Up until 1981 Evansville had only exceeded 23 inches of rain in a season 1 time, during Winter of 1949-1950. Just since 1981, Evansville has exceeded 23 inches of rain 4 times.

Evansville IN Summer June-August

Top 10 Wettest
Rank     Precipitation (inches)     Year
1     19.83     1977
2     17.60     2006
3     16.49     1958
4     16.32     1950
5     16.08     2005
6     15.98     1945
7     15.86     1959
8     15.60     2000
9     15.59     1969
10     15.45     2001

*4 of the top 10 wettest just since 2000!
Evansville IN  September-November Fall

Top 10 Wettest
Rank     Precipitation (inches)     Year
1     19.16     2006
2     19.01     2011
3     17.64     1996
4     17.28     1925
5     17.15     1984
6     16.15     1945
7     15.97     1993
8     15.72     1919
9     15.71     1910
10     15.66     1985
*6 of the top 10 wettest since 1981
*The 2 wettest were in the last 10 years going back to 1897
*3 wettest in the last 20 years
Evansville IN December-February Winter

Top 10 Wettest
Rank     Precipitation (inches)     
1     24.38     1949-1950
2     18.76     1936-1937
3     17.34     1915-1916
4     16.75     1999-2000
5     16.28     2007-2008
6     15.96     1948-1949
7     15.82     1922-1923
8     15.67     1951-1952
9     15.25     1961-1962
10     15.24     1906-1907

*Note 1936-1937. This which included record rains in January 1937 and the historic flooding on the Ohio River that year.
*Only 2 of the top 10 have occurred since 1981
*Recent Winters, unlike the other 3 seasons of the year(especially Spring), have not featured much heavier precipitation in this area.

This data is only for one location but it confirms what I knew already from continual observations of the US Cornbelt and surrounding areas since the 1980’s.

Interestingly, I believe that part of the increase in precipitation during the growing season is the result of a “micro climate” created by many tens of millions of acres of tightly packed rows of corn(twice as dense as 4 decades ago) that contribute significantly to low level moisture from the increase in evapotranspiration.

This has also resulted in warmer minimums at night, with the elevated dewpoints. Astute NWS forecasters, aware of this dynamic, will sometimes adjust the local forecast to account for what stage the corn plants are in.


I would say that when this effect is maximized, in late June and July, dew points across half a dozen states will be elevated by 5 deg. F or more.

This is a different kind of human caused climate change. Is it detrimental?
I think it has reduced extreme heat/day time max’s and increased rains to the benefit of the crops.
Lows at night that stay well above 70, however during and especially after pollination(during kernel fill) cause accelerated maturation(often referred to as heat fill) which means the corn plant does not have as much time to fill kernels.

The longer it takes to mature after pollination, the more time and energy can be diverted into filling kernels(and the plumper they get)……….with the exception of an early damaging freeze that is an extraordinarily rare event(1 out of 25 years for a state like Indiana).

Mike Maguire

Despite the slight increase in heat fill in corn plantsfrom elevated night time temperatures(causing smaller kernels in some years, at some locations) and an increase in heavy down pours, the weather and climate for growing corn, especially when we dial in the additional CO2 over the past 4 decades has clearly been the best in at least 1,000 years…………when temperatures were likely similar.

Going from 1988 to 2012 between major widespread droughts in the Cornbelt was a record 24 consecutive seasons. Record corn and soybean production/yields continue to exceed expectations, not in spite of but because of “climate change”.

This is not just a US Cornbelt phenomena either:

Boy, do I remember the ‘88 drought. Had just bought my Wisconsin dairy farm three years before. A Timber cruiser hoping for city boy luck came through winter before and offered $1000 per bole for 12 old mature white oaks on the off-odd 40 acres across from the ~1880s cabin core of the farmhouse. (white oaks are furniture wood plus crowns for bathroom tissue. Older ones are tall and straight and thick, ideal for furniture). I turned him down since already loved that little hunting section, not more than a few acres total. That summer drought, oak wilt set in on all 12 old stand trees and over the next year killed them all, Most expensive firewood I ever laid in on the farm—but lots of it. Next most expensive was a whole truckload of wild black cherry downed by a winter ice storm the next year. Had the cherry boles snaked out with tractor and logging chains and stacked as carefully measured 8’ pluss logs. Problem was, ‘only’ one semi truck load, so the logging company passed on expense of pickup. Made some beautiful furniture and firewood. A second dairy farm learning experience. There were many more this past 30 plus years.

Michael Jankowski

Well it has been documented that urbanization tends to increase rainfall thanks to the urban heat island effect and possibly aerosols. The effect tends to be downwind, of course.

Can storms moving west-to-east across St. Louis (which seems to be the normal flow) affect Evansville? Enhanced by the St. Louis UHI and greater Mississippi River flows?


IOW, the theory which predicts heavier (more intense) rainfall due to warming does not hold water.


Isn’t a lack of increased rainfall proof that climate change isn’t happening?

The increased rainfall is hiding in the deep oceans (:-))


The rainfall in Arizona is a no-brainer. It was, is, and will always be a desert climate in areas below 6000 feet MSL.

Local evaporation like you might get in Florida or the tropics of course is not involved in the precipitation production here in Arizona. The air is too dry.

The bulk of Arizona’s rainfall comes in atmospheric river-like flows from the Pacific. There has long been recognized a pressure pattern see-saw between the desert SW and the Pacific NW.

When Seattle to Portland is experiencing well below normal rainfall, the SW US is almost always getting drenched. And vice versa, like now.

If it’s less there, it’s more here.

Hence, my connection to the Tombstone grave marker “no Les, no more” pun.

But one also has to understand the role of surface heating that drives the unstable atmospheric lifting during monsoons in July-August. When sufficient moisture is pumped in from the Pacific during those months, the SW surface thermal heating drives explosive convective growth.


Eric Worrell also wrote this:

“parched soil often can’t absorb water until it has been soaked repeatedly by rain.’

Eric, I disagree with you at least here in Arizona. The rain water and snow meltwaters do mostly soak into the deep sandy soils to recharge the valley aquifers. The countless streams that flow out of the mountains and hills drains into sandy and rocky soil channels and disappears to the aquifers. The Spanish call the dry sandy river beds “arroyos.” The gringo name for them is “washes”.

130 years ago here in Arizona the aquifers in the valleys were only a few dozen feet below ground. Those rivers and larger streams like the Santa Cruz and San Pedro (and the now-dry Rillito River which flows to the Santa Cruz at Tucson), which were the lowest channels in the generally north running valleys to the Gila River were almost perennial flows. But ground water pumping and pumping for the mines has changed all that, forever. (Or at least until humans are no longer pumping the ground water.)


The mountains in Southern Arizona extend up to 9,000 feet plus (Mt Graham is just over 10,000ft). The valleys are filled to about 5,000 feet thick layers of sediments. Some places they extend down to almost 10,000 feet of sediments below the current day surface. Water fills the pore space.

There is a vast amount of water under the sands and gravel deposits in the gravel filled valleys of So Arizona. Below a certain level (~1,000 feet) though the ground water turns too mineral- and salt-laden for fresh water use.

This all goes back to what geologists understand about how environments form over deep time. That is something that is lost on a physicist like Michael Singer. He sees the present, and doesn’t understand that knowing the deep past tells us that modern climate change is just very likely at natural variation.

But then there’s no sensationalist stories and/or grant money in a natural variation explanation of current day climate.

Good posts Joel.


One of the great things about WUWT. Lots of good local information, observations and stories. Thanks to Joel and others.


Climate constipation from Cardiff has set in.

Gunga Din

That would be a nice change from the diarrhea of the mouth we get from the CAGW crowd.

Ross King

These Sinecure..Retentive so-called Climate Scientists, aka Snake-Oil Salesmen and Data Mannipulators, will seize on any vestigial report of “Change” (even if it is from yesterday) to claim that AGW is a threat to humanity.
They are in cahoots with MSM media in a symbiotic relationship based on Sky..Falling Crisis from one minute to the next.


daveburton commented: “Longer, less-intense rainfall events would increase absorption of water by the soil, replenish groundwater, and reduce erosion, compared to the opposite trend. What’s not to like about that??”

Exactly. Common sense. (how did this same response get attached previously???? It was supposed to be a reply to the post quoted)


Perhaps instead of climastrology, we could have a look at what the result on rainfall patterns was when it was warmer in the past?
The only reason one might decide that some unreliable models might be the way to go is if one is proceeding on the fiction that it has not been warmer, much warmer, in the recent past.
We know it has been warmer.
And we have good dendrochronological records of rainfall for that area of the world.

Steve Oregon

The latest Lake Powell elevation projection shows a healthy, stable and even increased level ahead.
comment image

So much for the doomsdayers who were so sure the lake was drying up.
….”Further, climate change scientists have painted a bullseye on the Southwest U.S., indicating that it will get hotter and drier, with even less flow into the Colorado River. The lead investigator in the in-progress Colorado report has even said, “I haven’t shown the climate change hydrology because it just scares everybody.”

Many more:


“”climate change scientists have painted a bullseye ”

Well we have seen how accurate their models are, so I’d say that SE US is pretty safe.

They can’t hit the side of a barn !!

Extreme Hiatus

They just adjust the bullseye to wherever the bullet hits. They’re expert Marxmen… I mean Marxpersons of course.

adrian smits

Question. If the planet is between 7 and 11% greener than it was in 1978 would that not mean that the extra c02 which supposedly caused this is also causing its own negative feedback because greener is cooler?

Dr. S. Jeevananda Reddy

When there is no global warming to recon, how could anybody say global warming influencing the precipitation.

Meteorological department have been publishing the frequency distribution of precipitation under different rainfall ranges.

Also, natural variability in precipitation changes the precipitation pattern in the below and above the average cycles.

At all India level, 2002 and 2009 are severe drought years with 0.81 and 0.79% of the average and temperature gone up by 0.7 and 0.9 oC.

Changes in terrain modifies the rainfall pattern.

Truncated data series show the results what even you wanted. In fact this is what the inter-state river disputes tribunals are doing. To favour a state they select that period of the series and infer conclusions detrimental to other states. This is happening in the Krishna River basin. Here 114 years data series are available to the tribunal but used 47 years that is part of above rainfall period of 132 year cycle. To infer some other unethical issues used 26 years data series. In fact while doing probability estimates, one must test whether the data series follo the normal distribution and skewed distribution [positive or negative]. 114 years data series followed normal while 47 years data series followed positively skewed. Unfortunately central water commission members released a report on 26th November 2017 — followed the same path as tribunal — and used only 30 years data and found mean and 75% values abnormally high.

Dr. S. Jeevananda Reddy

Dr. S. Jeevananda Reddy

To provide more clarity on the above comment of mine,see the note a part of my mail submitted to central water commission of India under ministry of water resources:

Plenty of water in Krishna: A false alarm by CWC

Indian rainfall is seasonal. To conserve water, Rajas and Maharajas built tanks, later on Krishna River: during British rule built Prakashmam Barrage (1857), K.C. Canal (1870), Sunkesula barrage, etc; Nizam Nawab built reservoirs like Rajoli Banda Barrage (1958); after Independence to India the First Prime Minister of India, Pundit Jawaharlal Nehru gave importance to dams as he considered them as modern temples and built Tungabhadra dam (1953), Nagarjunasagar Dam (1967), Bhima Dam (1980), Srisailem Dam (1981), Narayanpur Dam (1982), Jurala Dam (1995), Almatti Dam (2005), Pulichintala Dam (2013), etc. They are providing water for irrigation, drinking, industry and production of power at very low price.

The annual rainfall presents 132-year cycle with 66-years each of the below and above the average pattern of the sine curve. 66-years prior to 1935 presented below the average pattern in which 24 years received Deficit and 12 years Excess rainfall — Deficit means 110% of the average –; 66-years from 1935 to 2000 presented above the average pattern in which 24 years received Excess and 12 years Deficit rainfall. The water availability in Krishna also followed this pattern. The average along with the lowest and the highest rainfall in met sub-divisions of three riparian states are as follows:

Met Sub-division Rainfall, mm
The lowest/year The highest/year Average

Rayalaseema 225.7/1876 1228.3/1874 709
South Interior Karnataka 515.7/1876 1173.6/1882 878
North Interior Karnataka 413.5/1876 1182.1/1892 833
Madhya Maharashtra 344.9/1899 1108.2/1878 735
Marathwada 283.8/1871 1501.3/1892 833
Vidarbha 445.1/1899 1532.4/1936 1094

Very low rainfall zone and also in rain shadow zones of the Western Ghats, namely Sangly-Bellary-Anantapur zone, more than 50% of the years experience drought.

That means the water availability is highly variable with year to year and follows a natural rhythmic pattern. To achieve sustainability in water availability to different projects, government of India appointed Bachawat Tribunal and [BT] in 1969 and in 1976 it submitted its report. As per this award still Krishna water is distributed among the three riparian states, namely Maharashtra, Karnataka and undivided Andhra Pradesh [UAP]. Later government of India appointed a second tribunal, namely Brijesh Kumar Tribunal [BKT] in 2004/06 and it submitted its report in 2013; but Supreme Court issued stay on this award implementation as it is biased towards UAP.

BT used 78 years data series [1894-95 to 1971-72] which was available to him at that time – all the three riparian states accepted the data series. In this 41 years forms poor rains and 37 years good rains of 132 year cycle. BKT used 47 years data series [1961-62 to 2007-08] though 114 years data series [1894-95 to 2007-08] were available, in which 40 years form good rains and seven years forms poor rains of 132 year cycle – UAP disagreed on using this data. Because of this the mean of BKT is more than BT by 185 tmcft. Though BKT selected 47 years data series but in reality used five different data sets to prove his unethical inferences.

BKT for permitting to raise Almatti Dam height and legalize illegal projects under Tungabhadra along with these two, more water goes as groundwater and evaporation — In the tribunal awards groundwater use is not a part of water available – KBT pronounced that UAP will get 1530 tmcft; and thus even after deducting 230 tmcft allocated to Almatti still UAP will get 1300 tmcft, which is more than 811 tmcft allocated to UAP by BT.

To show how they arrived at 1530 tmcft on an average they used 26 years data series [1981-82 to 2006-07] of Bhima-Krishna River reaching Jurala dam. This was stated to be 932 tmcft on an average. To this added 190 tmcft from Tungabhadra and 350-400 tmcft locally available in UAP. To this if we add the water allocated to Karnataka and Maharashtra it will be 3050 tmcft.

On probability curve of 47 years data series, 3050 tmcft is available at around 24%; but from the 26 years data series [which is part of 47 years data series] probability curve it is available at around 18%. The values at 75% probability and mean are around 2000 and 2400 tmcft; and the same for 47 years data series are 2173 and 2578 tmcft.

Out of the 26 values 8 are below 2000 tmcft and 5 are more than 3000 tmcft; 13 points each are on either side of 2400 tmcft [at 50% probability level] and thus they show that the data series followed normal distribution pattern; and in the 47 values, 28 are on higher side and 19 are on lower side of the mean [2578 tmcft]. It s a positively skewed distribution – because of this mean is available at 58% probability level — and thus estimates are biased. The estimates are reliable only when it follows normal distribution in which mean coincides with 50% probability level. 114 data series follow this. 75% probability means 75 years out of 100 years.

Similar to BKT, Central Water Commission (CWC) used 30 years data series [1985-86 to 2014-15] in which 16 years are in good rainfall period and 14 years are in poor rainfall period. 22 years of 26 years data series formed part of the 30 years. And yet CWC claimed plenty of water available in Krishna River. They say that 2522.52 and 3144.42 tmcft of water available respectively at 75% probability and Mean. 3144.22 tmcft at mean is nearly same as that of BKT arrived to raise the Almatti dam height [3050 tmcft]. If they are correct then more than around 1000 tmcft must enter the Sea most of the years when we look in to the capacity of the dams in UAP. It is not happening.

According CWC the highest water availability of 4165.42 tmcft was in 2010-11. However, even higher value of 4194 tmcft was recorded in1975-76. They say the lowest 1934.89 tmcft was recorded in 2002-03. According to BKT this was shown against 2004-05; and in 2002-03 and 2003-04 recorded 1239 & 1253 tmcft [the lowest observed as 1007 in 1918-19; also 1125 in 1899-1900; 1273 in 1905-06]. That means CWC showed around 700 tmcft more. How can it will be possible when rainfall, water used in Delta and water entered in to the sea are against this inference of CWC. For example:

In undivided AP out of 23 districts in 2002-03 received deficit [< 90% of the average] rainfall in 16/15 districts during the southwest/northeast monsoons — In 2002 and 2009 with severe drought conditions of 81 and 79 % of average rainfall presented a raise of 0.7 and 0.9 oC, respectively at all India level –. . It is also a fact that many years after 2001 Nagarjunasagar Dam wasn’t reached to its full capacity on many years. Also, during 2001-02 to 2005-06 water availability were 1836, 1239, 1253, 1934, 3624 tmcft and Delta received 190, 118, 84, 137 & 187 tmcft against the allocated 181.2 tmcft; and water entered the sea were respectively 111, 13, 12, 23, 1273 tmcft.

All these clearly show it is a false alarm created by CWC and as well BKT to serve the vested interests.

CWC playing game to ask the Supreme Court to lift the stay order on the tribunal order.

Dr. S. Jeevananda Reddy
Formerly Chief Technical Advisor – WMO/UN & Expert – FAO/UN
Tel. 23550480

michael hart

The warmer world=wetter world (except when it isn’t) argument has always been so oversimplified as to be worse than unhelpful.

If pushed on the matter, I’m sure that even a climate scientist would admit to noticing that much of the evaporation and much of the precipitation doesn’t occur in the same place or at the same time. It is everything that happens in between that is both important and hard to predict. I think they relish the uncertainty really, because it makes it easier for them to get away with claiming whatever they like in their ignorance.


“Lecturer in Physical Geography Michael Singer has noticed that climate hasn’t brought greater precipitation, as Trenberth predicted it would”

“U.S. Precipitation Change

Since 1900, average annual precipitation over the U.S. has increased by roughly 5%. This increase reflects, in part, the major droughts of the 1930s and 1950s, which made the early half of the record drier. There are important regional differences. For instance, precipitation since 1991 (relative to 1901-1960) increased the most in the Northeast (8%), Midwest (9%), and southern Great Plains (8%), while much of the Southeast and Southwest had a mix of areas of increases and decreases.”


If rainfall is an indicator of climate change, perhaps the change in climate isn’t as catastrophic as they’re pretending it is.


I don’t see why rainfall in a particular spot on land would have anything to do with the temperature trends at that spot. The weather systems bringing in the rain are mostly coming from off the ocean, which is where temperature trends theoretically might have affected how much moisture the atmosphere was acquiring.
Seems like the humidity readings and sea surface temps over the Gulf of Mexico and the eastern Pacific would be what might hypothetically correlate to rainfall over the Arizona deserts.

Gunga Din

I would think that rainfall in a desert would only be a problem if you forgot your umbrella. … or if you want it to remain a desert.

PS I thought we now had “monsoons” in that area? Aren’t monsoons intense?


Monsoon simply means a seasonal reversal of the wind flow, which leads to an increase in moisture and rainfall.
I think many people perceive it to mean a big storm, but that is not the actual definition of what a monsoon is.

Gunga Din

Growing up and until the last year, I’d only heard “monsoon” in reference to places like India and Southeast Asia. “Monsoon Season” was weeks or months of rain. (Think Forrest Gump).
Never heard it reference to anywhere else. Even Wikipedia’s article (at the time I read it) said applying the term to weather patterns in North America was controversial. (Sort of like saying Siberia experienced a “Nor’Easter” or “Santa Anna” winds.)


I first heard in used in reference to the desert southwest when I was there, and saw the term being used by all of the local meteorologists on various news programs in various cities all over the region,
I have since heard it used more frequently and in other places.
For another example, look at the newest modifications to the climate classifications of Florida.
The region of the southeast Florida coast is now listed as a monsoonal climate.
It living here, I can tell you, from October to April or May or so, the predominant wind direction is from the west and northwest, and this is also called the “dry season”.
The rainy season begins at some point in the spring, and is marked by Easterly and southeasterly winds (the trade winds), increased humidity at the lower and mid levels of the atmosphere, and frequent rains, typically daily (although all spots do not get rain on all days, there are usually some showers around).
This is called by everyone “the rainy season”.
If the winds come out of the west in the rainy season, this is called a reverse flow, and the pattern of daily rain is altered, with large heavy showers in the afternoon on the east coast, and typically lighter and shorter morning rains on the west coast. More commonly, when the wind is from the east, there are more often lighter showers in the morning on the east coast, and heavy rains in the afternoon on the west coast.
These patterns repeat, day after day, year after year…although people that have never been here often never are even aware of it.

The usage is not controversial in my learning and experience. This was the textbook definition given when I took several years of classes in physical geography, meteorology, and climatology at USF in Tampa.
Although I have only recently seen the climate of Miami thus classified, it does fit the pattern.

“Tropical monsoon climates are most commonly found in South and Central America. However, there are sections of South Asia, Southeast Asia, Africa (particularly West and Central Africa), the Caribbean and North America that also feature this climate.”


The thing is, for the purpose of climate classification, a precise definition of each climate zone must be given.
Any location that then meets this definition is therefore classified according to that definition.
Since the particulars are carefully defined, areas that are on the edge of being one or the other can then shift with even slight variations in the 30 year averages.
You see, there really is and always has been climate change, as anyone who has studied these things and has a good memory has long known.

Gunga Din

I followed your Wikipedia link for “Tropical Monsoons” and searched for just “Monsoons”.
Neither are what I had read a year or so ago. No mention of applying the term to North America as being “controversial”.
But, hey, it is Wikipedia.
Importing disastrous weather terms? 😎
(A layman’s impression.)


The funny part is, no one in Florida or the Caribbean uses the word monsoon to describe the changing rainfall patterns throughout the year. Everyone just says dry season and rainy season.
But it is classified as such according to the official definition.
And in the desert southwest, everyone uses the term to describe the summer rainy season, even though the region does not climatologically meet the official definition.
Also interesting to note that one can look up Koppen Geiger climate maps in several different sources and see various areas listed quite differently, even for the same time period (1901 to 2010 for example).
But such is settled science.
For those of a logical bent who appreciate the value of consistency, it is most unsettling!


Yes, I found the same lack of consistency.
The first thing I did was look up the word in a regular dictionary, knowing from memory what I had learned from textbooks in college, and subsequent readings.
In the first three I checked, it only referred to the southeast Asia monsoon. I suspect that this is where the word originated, and was subsequently applied to any climatic region meeting the definition that was originally defined to match those regions.
Sort of like saltine crackers or Kleenex tissues, the word had a specific origin but now has a broader assignment.
And the various wiki articles do not match up well either, with one declaring that the monsoon climate is most represented in South and Central America, and only lists Asia as an additional area with monsoons.
From the “Tropical Monsoon Climate wiki page: “Tropical monsoon climates are most commonly found in South and Central America. However, there are sections of South Asia, Southeast Asia, Africa (particularly West and Central Africa), the Caribbean and North America that also feature this climate.”

The North American Monsoon page only mentions a reversal of winds in passing, and does not define a monsoon as having that feature as being central to the definition.

If you use a source which describes the Koppen Geiger classifications, the exact definition does not mention wind at all: “Am = Tropical monsoon climate; driest month (which nearly always occurs at or soon after the “winter” solstice for that side of the equator) with precipitation less than 60 mm (2.4 in), but more than 4% the total annual precipitation.”
However, the explanation section of that classification does describe the reason for the above as being due to a change in wind direction. I am pretty sure that a seasonal reversal, or nearly so, is a more complete description. Nearly everyplace on Earth has shifting patterns of winds as the seasons progress. Even the deep tropics with nearly constant weather throughout the year have a shift in winds as the ITCZ fluctuates from north to south and back again.

But we must ignore all of that these days…the science is settled.
With the additional exception of the classification system itself…many do not find it logical of helpful to use a system that classifies the entire eastern US, from central Florida to south Texas and from Nebraska to southern New England as one climate zone. That aint settled neither.
Still looking for the ACTUAL settled stuff.


…or helpful…


Taking a look at the way each letter in the Koppen system is defined, it is easy to see why there could be controversy and certainly changes.
“Driest month no more than 60mm but at least 4% of annual total precip”?
That is very specific, and so the map will look different depending on what 30 year period one uses (and I suppose if one uses raw or adjusted data!) and whose rain bucket gets the nod.
And the letters mostly all have the same sort of specificity. Some are even more specific and downright arcane…like the B sub-classifications.
I am wondering how they make a map with .5 degree pixels/grid size. There are not enough rain buckets and thermometer readings to do the whole world to that fineness…not even close.

John in Oz

Can you imagine how long the comments for this topic would be if the science was not already settled?

When I consider the number of contrary points made by the many contributors I have to wonder how any ‘consensus’ could be formed for any climate-related topic.

Gunga Din

That’s because all the “Genuine Climate Scientist” are over at RealClimate,con. 😎

John in Oz

You forgot the tag

In case you were serious, in business studies there is a concept called the ‘comfortable clone’ syndrome whereby people hire others of like mind because they are averse to differences to the corporate ways of thinking. This is considered a BAD situation.

At least on this blog there are differences that can be debated without fear or favour (sic – Aussie spelling)

Gunga Din

Hi, John.
No, I wasn’t serious. And, yes, I didn’t use a /sarc tag. I thought the “8-)” would commuicate the same.
(Along with “RealClimate,con.)
Sorry for any misunderstanding.

PS You said, “At least on this blog there are differences that can be debated without fear or favour”.
Absolutely correct and something to be thankful for.