The Weather Isn't Getting Weirder Or More Extreme.

Just one beside-the-point comment...

Atmospheric moisture is a necessary but not sufficient condition for heavy precipitation; large-scale lift is required. Without lift (ascension), the worst that will happen is drizzle or light snow flurries, regardless of how much moisture there is in the atmosphere.

It is true that warm(er) air will hold more moisture, but that doesn't necessarily result in more snow/precipitation.

 

If you look at the actual data there is not more precipitation. Those comics are not written by people that understand scientific method and the data. They are written by people like those that blamed katrina on not signing kyoto, when it is clearly ridiculous. Katrina was a big disaster because of man made problems like destruction of wet lands and creation of a deep water channel while building under engineered levies so people could live where storms hit. It was made worse by awful response from the city, state, and federal disaster folks that should have had a better plan and response.

Globally warmer temperatures seems to have an impact on moving where the precipitation is, the data is not there one way or the other to claim scientifically that it is concentration it. The movement can be studied and will change the locations of where these disasters are likely to hit. This analysis does not need to assign blame to deniers or china. Let us look at the possible effects of kyoto policy to say remove ghg by killing manufacturing in europe and moving it to china and india. Did it actually increase ghg? International treaties should be evaluated on their macro not micro effects.

 

That was just a little meteorology 101.

As an atmospheric scientist/meteorologist, I'm just dissatisfied with the explanation for "more snow in the mid-latitudes" is that "warm air holds more water".

In my opinion as a met, the explanation for this season's "extreme weather" is the persistent weather pattern of a strong omega block over the north Atlantic. Blocking patterns are nothing new; it just happen to set up in a way that affected population centers this year.

 

The simple explanation was meant for people who think that heavy snow proves that there is no global warming. In fact, of course, it is entirely consistent.

 

Yep, there is not evidence that it was caused by global warming. I was just adding that the data says that global warming is not causing more precipitation only shifts in precipitation.

Absolutely, the heavy snows do not prove anything about global warming, they are just weather. The deniers, whose faith in NO global warming should understand that, but I don't think the cartoon will be taken that way. The believers, whose faith in global warming disasters, seem to claim snow proves global warming or climate change or whatever today's religious term is. The snow doesn't do anything for or against either theory. World wide temperature measurements are the evidence of global warming, not hurricanes and snow.

 

It amazes me that the term "global warming" is still being bantered about. Each time we have snow or cold in the warmer climates all I here is that it is proof that global warming doesn't exist. For those who can't see beyond this quarter's profits or their noses for that matter, I think we should be talking climate change. Then maybe, just maybe they will be able to understand the difference between climate and weather.

 

There is some speculation that the NAO changes evident the last couple years is being affected by low ice levels in the arctic...

Future of Arctic Sea Ice and Global Impacts - Warm Arctic - Cold Continents

 

OK, now we are discussing global precipitation trends. Austingreen may have come to his conclusion by reading Adler et al 2003, The Version-2 Global Precipitation Climatology Project (GPCP) Monthly Precipitation Analysis (1979–Present), Journal of Hydrometeorolgy 4: 1147-1167.

Which handles the situation until 2002. Might not have seen Dai et al 2010,

Drought under global warming: a review, WIREs Climate Change (lacking page numbers but here's the DOI DOI: 10.1002/wcc.81

That one (and the refs cited) show that wet areas have been getting wetter ad dry areas drier. Also projects futre trends with climate models, which will not of course appeal to all readers here.

There has actually been a lot published on regional precipitation trends, and they are far from the most difficult papers to read. After all a rain guage need be nothing more than a soup can and a ruler.

Anyway, as usual I cannot tell whether this is a topic of particular interest here, or whether y'all are just driving by.

Wxman gets points for adding 'uplift' to the discussion. It is the sort of thing that we'd all learn in meteorology courses.​

 

In addition to being the hottest year in the instrumental record (though not statistically significantly warmer than 2005 per NASA or NOAA), 2010 was also the wettest.

"Global precipitation in 2010 was well above the 1961–1990 average, ranking as the wettest on record since 1900."

I think that's "since 1900" because that's when the timeseries starts, but I don't actually know that. Nor can I even guess how they measure it. But that's NOAA saying that.

State of the Climate | Global Analysis | Annual 2010

Looks trend-y to me, but I haven't analyzed it, nor have I seen any formal analysis. That said, most of the green is on the right side of the graph.



Unsurprising, really, given that global specific (absolute) atmospheric humidity should (and is) rising as the temperature rises. I think the humidity data were published a while back in Nature. Here's the graph:





The interesting thing is the magnitude -- more than 2% increase in atmospheric water vapor in less than 30 years. Short timeseries and all, but that's still pretty impressive. Also, pretty cool how the 1998 El Nino temperature spike shows up clearly in the water vapor data.

I can't find the original research, but here's a popular press writeup.

Global Warming Causes Humidity Levels To Rise - Green Diary

I couldn't tell you whether the change is statistically significant, but at least by eye, it seems incorrect to assert that global precipitation is unchanged. Near as I can tell 2010 set the record in the instrumental era. This hasn't gotten as much attention as temperature, but that doesn't mean it is unchanged.

 

I hunch it's a fairly wide audience. I, for one, am very interested in hearing more from someone like you who knows what they're talking about, and far less from people who think 'climate change' is a religious term, and those who bait the discussion by saying "Sure is cold today. So much for global warming. Ha ha."

In other words, Tochatihu, yes, please. It would be wonderful to have a serious discussion.

The distinction between the increasing range of extremes and averages that may or may not be changing significantly is something I am interested in learning more about.

 

Thanks, that drought review paper is excellent. Also good to be reminded that precipitation is different from average soil moisture, as evaporation increases with temperature.

The projection of a US Midwest dustbowl is probably the single prediction of the model ensembles that leaves me most depressed. Although, as I understand it, much of the US midwest was essentially desert by the end of the Holocene thermal maximum, so it's not like that ought to come as any great surprise. That said:

1) I was taught that the decline of Greco-Roman civilization was driven in large part by the decline in arable land. The US has huge effective grain surpluses now (because 70% of what we grow goes to animal feed, and that would not have to take place in the event of an emergency), but how would that look absent the Midwest?

2) For me, the NY Finger Lakes region is looking like a good retirement destination. Basically, the rain moves north as the earth warms and the Hadley cell expands. You want a verdant climate for your grandkids, better start re-thinking American tradition of moving south to retire.

 

Thanks Tochatihu,

Most of what I have read on the matter did indeed come from the early 2000s, but then again if we are talking global weather, things could not have changed very much ;-) I am skeptical on the matter of harsher storm, but definitely open to the evidence.

I've only really looked at teh sumary and glanced at the maps. I'll read the report. The takeaway that I got from that is we need to look at our farming as crops and good land are shifting. I did not realise it also had things to say about the intensities of storms.

I am also more open to weather and storm changes having correlation with global warming if the climate is influenced by the melting artic ice caps as it seems to be in england. The Dallas ice storms just seem to be normal dallas percipitation, that happened at a cold time. In Austin we had the longest period bellow freezing in 40 years, and although unusual I would not blame that on gw.

T,
Just out of curiosity, what is your area of research?

 

I don't remember any comprehensive studies on precipitation intensities, looking backwards. There are several modeling studes on that but well not everyone grooves on the models. I think we will see more about that from the climate reanalysis project.

I study biogeochemistry which is just the $10 word for nutrient cycling. These days much of the focus is on the carbon cycle. This field can be very multidisciplinary which is why I dabble in molecular genetics to meteorology. But if you want to know how Hadley cells form, for example, best ask wxman about it.

 

Getting back to the original post, we can now read Compo et al.'s response to the WSJ

Severe Weather Is Driven by Many Factors - WSJ.com

It strikes me as quite civil. Kinda makes me want to hack into Compo and his coauthors' email and see what they really think...

 

Piers Corbyn has an independently audited accuracy of 85%.
Traditional science has ZERO % long range.( and probably 50-50% short range)
He fully explains his methodology online.
But if he was using traditional methods his accuracy would be a lot closer to zero .
His method is revolutionary.
Ill ask again ,how can an extreme weather event be predicted months in advance by observing the Sun and Moon,unless that event was caused by the Sun and the Moon?
A correct prediction is full validation of the hypothesis.
85% correct predictions over a period of many years is proof of causation.

 

He could have gotten the same results reading chicken entrails. Come back when two or more independent sources can do the same thing with the exact same methodology.

 

If weather predictions don't warm you, have a look at some earthquake prediction sites

Earthquake Prediction California, San Francisco, Los Angeles, recent, earthquake, San Diego, Eureka, San Bernardino.
Earthquake predictions, largest regional earthquakes

don't seem to disclose their methods, while

IIEPT RAS

does, to a degree. One wonders why geologists in general do not jump on the bandwagon? I do not know you tell me. Maybe this does not quite belong in enviromental discussions. But see also

Animals and Earthquakes

for some potential quake/weather interactions.

 

I ask again,,, how does the moon effect the weather?

 

I'm not so sure. That's a strong correlation, at least, but what's the method of causation? I can understand the Sun affecting our weather, and the moon influencing our tides, but...

Perhaps you can tell us what Mr. Corbyn says about how it works.

 

Seems like (within the narrow confines of established science) a lunar effect would have to be based on tidal pull. The ocean and atmosphere certainly slosh around daily because of that. An additional solar effect may be related to varying fluxes of charged particles in the upper atmosphere. None of that is entirely new, but Coryin may have come up with some new super secret way to look at the data.

If the method is so good, I have no doubt that people will purchase his predictions. However I would stop short of saying that the hypoethesis is validated, or that the causation is proven. Correlation is not causation (so the saying goes).

Also, if I could show an 85% success rate for heat flux predictions based on 3 oC warming per CO2 doubling, would all here take that as proof? Oh the temptation...