From the “models can make you believe anything” department comes this breathless doom-laden press release from the same school that brought you the big wheel of silly climate model results.
Study finds more extreme storms ahead for California
New technique predicts frequency of heavy precipitation with global warming
On December 11, 2014, a freight train of a storm steamed through much of California, deluging the San Francisco Bay Area with three inches of rain in just one hour. The storm was fueled by what meteorologists refer to as the “Pineapple Express” — an atmospheric river of moisture that is whipped up over the Pacific’s tropical waters and swept north with the jet stream.
By evening, record rainfall had set off mudslides, floods, and power outages across the state. The storm, which has been called California’s “storm of the decade,” is among the state’s most extreme precipitation events in recent history.
Now MIT scientists have found that such extreme precipitation events in California should become more frequent as the Earth’s climate warms over this century. The researchers developed a new technique that predicts the frequency of local, extreme rainfall events by identifying telltale large-scale patterns in atmospheric data. For California, they calculated that, if the world’s average temperatures rise by 4 degrees Celsius by the year 2100, the state will experience three more extreme precipitation events than the current average, per year.
The researchers, who have published their results in the Journal of Climate, say their technique significantly reduces the uncertainty of extreme storm predictions made by standard climate models.
“One of the struggles is, coarse climate models produce a wide range of outcomes. [Rainfall] can increase or decrease,” says Adam Schlosser, senior research scientist in MIT’s Joint Program on the Science and Policy of Global Change. “What our method tells you is, for California, we’re very confident that [heavy precipitation] will increase by the end of the century.”
The research was led by Xiang Gao, a research scientist in the Joint Program on the Science and Policy of Global Change. The paper’s co-authors include Paul O’Gorman, associate professor of earth, atmospheric, and planetary sciences; Erwan Monier, principal research scientist in the Joint Program; and Dara Entekhabi, the Bacardi Stockholm Water Foundations Professor of Civil and Environmental Engineering.
Large-scale connection
Currently, researchers estimate the frequency of local heavy precipitation events mainly by using precipitation information simulated from global climate models. But such models typically carry out complex computations to simulate climate processes across hundreds and even thousands of kilometers. At such coarse resolution, it’s extremely difficult for such models to adequately represent small-scale features such as moisture convection and topography, which are essential to making accurate predictions of precipitation.
To get a better picture of how future precipitation events might change region by region, Gao decided to focus on not simulated precipitation but large-scale atmospheric patterns, which climate models are able to simulate much more reliably.
“We’ve actually found there’s a connection between what climate models do really well, which is to simulate large-scale motions of the atmosphere, and local, heavy precipitation events,” Schlosser says. “We can use this association to tell how frequently these events are occurring now, and how they will change locally, like in New England, or the West Coast.”
Weather snapshots
While definitions vary for what is considered an extreme precipitation event, in this case the researchers defined such an event as being within the top 5 percent of a region’s precipitation amounts in a particular season, over periods of almost three decades. They focused their analysis on two areas: California and the Midwest, regions which generally experience relatively high amounts of precipitation in the winter and summer, respectively.
For both regions, the team analyzed large-scale atmospheric features such as wind currents and moisture content, from 1979 to 2005, and noted their patterns each day that extreme precipitation occurred. Using statistical analysis, the researchers identified telltale patterns in the atmospheric data that were associated with heavy storms.
“We essentially take snapshots of all the relevant weather information, and we find a common picture, which is used as our red flag,” Schlosser explains. “When we examine historical simulations from a suite of state-of-the-art climate models, we peg every time we see that pattern.”
Using the new scheme, the team was able to reproduce collectively the frequency of extreme events that were observed over the 27-year period. More importantly, the results are much more accurate than those based on simulated precipitation from the same climate models.
“None of the models are even close to the observations,” Gao says. “And regardless of the combination of atmospheric variables we used, the new schemes were much closer to observations.”
“Actionable information”
Bolstered by their results, the team applied their technique to large-scale atmospheric patterns from climate models to predict how the frequency of heavy storms may change in a warming climate in California and the Midwest over the next century. They analyzed each region under two climate scenarios: a “business as usual” case, in which the world is projected to warm by 4 degrees Celsius by 2100, and a policy-driven case, in which global environmental policies that regulate greenhouse gases should keep the temperature increase to 2 degrees Celsius.
For each scenario, the team flagged those modeled large-scale atmospheric patterns that they had determined to be associated with heavy storms. In the Midwest, yearly instances of summer extreme precipitation decreased slightly under both warming scenarios, although the researchers say the results are not without uncertainty.
For California, the picture is much clearer: Under the more intense scenario of global warming, the state will experience three more extreme precipitation events per year, on the order of the December 2014 storm. Under the policy-driven scenario, Schlosser says “that trend is cut in half.”
The team is now applying its technique to predict changes in heat waves from a globally warming climate. The researchers are looking for patterns in atmospheric data that correlate with past heat waves. If they can more reliably predict the frequency of heat waves in the future, Schlosser says that can be extremely helpful for the long-term maintenance of power grids and transformers.
“That is actionable information,” Schlosser says.
###
This research was supported in part by the National Science Foundation, the National Aeronautics and Space Administration, and the Department of Energy.
Written by Jennifer Chu, MIT News Office
PAPER: Paper: 21st century changes in U.S. regional heavy precipitation frequency based on resolved atmospheric patterns
http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0544.1
Ok, here’s some “actionable information”.
They failed to examine the null hypothesis, what sort of rainfall patterns would California get with a 4°C cooling?
In citing “…the team was able to reproduce collectively the frequency of extreme events that were observed over the 27-year period. ” They fail to note that they are only reproducing weather during a period of warming in California’s history. And since models are tunable, this could be little more than a self-tuned confirmation bias.
But here’s the real kick in the pants from California history: The Great Flood of 1862
The Great Flood of 1862 was the largest flood in the recorded history of Oregon, Nevada, and California, occurring from December 1861 to January 1862. It was preceded by weeks of continuous rains (or snows in the very high elevations) that began in Oregon in November 1861 and continued into January 1862. This was followed by a record amount of rain from January 9–12, and contributed to a flood which extended from the Columbia River southward in western Oregon, and through California to San Diego, and extended as far inland as Idaho in the Washington Territory, Nevada and Utah in the Utah Territory, and Arizona in the western New Mexico Territory.
The event was climaxed by a warmer, more intense storm with much more rain that was much more serious, due to the earlier large accumulation of snow, now melted by the large turbulent heat fluxes into the snow over the lower elevations of the mountains. Throughout the affected area, all the streams and rivers rose to great heights, flooded the valleys, inundated or swept away towns, mills, dams, flumes, houses, fences, and domestic animals, and ruined fields. An early estimate of property damage was $10,000,000. However, later it was estimated that approximately one-quarter of the taxable real estate in the state of California was destroyed in the flood. Dependent on property taxes, the State of California went bankrupt. The governor, state legislature, and state employees were not paid for a year and a half. 200,000 cattle drowned, and the state’s economy shifted from ranching to farming.
…
The floods were likely caused by precipitation from atmospheric rivers, or narrow bands of water vapor about a mile above sea level that extend for thousands of kilometers.
Prior to the flooding, Oregon had steady but heavier than normal rainfall during November and heavier snow in the mountains.
The weather pattern that caused this flood was not from an El Nino, and from the existing Army and private weather records, it has been determined that the polar jet stream was to the north as the Pacific Northwest experienced a mild rainy pattern for the first half of December 1861. The jet stream then slid south and freezing conditions were reported at Oregon stations by December 25. Heavy rainfall began falling in California as the longwave trough moved down over the state, remaining there until the end of January 1862 and causing precipitation everywhere in the state for nearly 40 days. Eventually the trough moved even further south, causing snow to fall in the Central Valley and surrounding mountain ranges.
What was the global CO2 level in 1862? According to The Keeling Curve at Scripps, it was about 260ppm compared to today’s 400+ PPM
So if global warming is caused by more CO2, and according to MIT, warmer times will cause ‘more extreme storms’, why have we not seen events like the one in 1862, or worse?
And what makes these events, when CO2 levels were lower, not worthy of them running the model backwards in time?
March 1907 and January 1909 Floods
Significant flooding on all major rivers in the Sacramento Valley. A record instantaneous flow peak was set one year, the record overall flow volume was set during the other. A total of 300,000 acres were flooded in the Sacramento Valley in 1907.
– Long-term Strategic Impact: The flood episodes resulted in an overhaul of planned statewide flood control designs. Previous designs were based upon Midwest experience, which relied upon confining rising rivers between levees. The concept of bypasses and overflow weirs had been suggested and rejected. Following the 1907 and 1909 record floods, a new Lead Planning Engineer was selected and the current California flood control design was devised.
1969 Winter Storms and Floods
Significant flooding on Central Valley rivers and reformation of Tulare Lake in the San Joaquin Valley as extended precipitation fell across the state. Heavy snow fell in all mountain ranges and the monthly rainfall record was set in Sacramento. Forty counties were disaster-declared.
Source: DRI
Personally I think their modeling is all wet, and just about as credible as the last doomsday climate model MIT produced:
Jobs for the boys.
For giggles, read this one.
Go to the USA maps near the end.
Notice the years.
All from discredited models.
Sadly, a product of MIT.
http://www.businessinsider.com/climate-change-effects-global-economy-gdp-2016-12
There is a fatal flaw beyond the 4C ‘assumption’ called out by Willis upthread.
I thought it curious that a paper published late in 2016 would end with observational data only through 2005. What happened to the intervening decade? That is an old Mann ‘hide the pause’ trick called out in essay An Awkward Pause. So researched it.
Starting 1979 is understandable– the satellite troposphere temperature era. NOAA ESRL says there there were 42 ARs in California from 1979- first week 2006. They bring up to 50% of California’s total precipitation, and cause virtually all its floods. I could not locate an official AR count since 2005 in a quick half hour google search, but just counting Pinapple express events reported in the local press through 2015 there have been only 4: 2008, 2010, 2014, 2015. This probably under counts California ARs. But, California has been in drought since ~2010, so a dearth of ARs compared to the previous period based on ESRL is a ‘fact’. Now look at the study method. A statistical correlation between CMIP5 large scale atmospheric patterns and actual ARs. The correlation will be higher in a period with more ARs. For max alarm, select a sample period for max effect so stop in 2005–not a subtle bias.
Overheat the model to get more large scale patterns, then goose the end result by careful sample period selection. As Heisenberg once commented about a quantum physics paper, so bad its not even wrong.
like to use the proper technical term, when I can. The word here is:
HOAX
If a model can’t replicate the past how can it predict the future?
Sounds like they’re using the climate models to predict weather. Interesting turn. As a Californian, I personally hope we do have more precipitation. I presume that will spare us from the droughts that the models also predicted.
When I was in graduate school in the mid-1970’s a friend of mine did his thesis research on weather map typing. Briefly the theory was that if you had a catalog of weather map types and knew what happened after each map type then you could forecast by matching the current weather pattern with a historical map type.
I have always wondered if the same technique could be applied to determining whether the frequency of severe weather is changing over time. There is a data set that goes back to, I believe, 1950 and I assume that computerized pattern recognition techniques have improved in the last forty years.
My question is why don’t the climate scientists use historical data instead of running historical simulations in their analyses?
Because historical data does not give them the “we are all going to die in a fiery flood” globall warmining results with which they continue to get phat checks from the government.
The use of “analog years” is a technique used for short term weather forecasts, weeks to months.
Here is one:
by Pete Parsons
This is from the Oregon Department of Forestry, now using the years 1983-84, 1992-93, & 1998-99.
If you look in a “picture dictionary” for weather forecaster that uses analog years, you will find a picture of Joe Bastardi & The WeatherBELL team.
It is irrelevant what the models say, we should not base policy on whacko models.
Correct. What we should be doing is preparing ourselves to be able to handle ANY climate extremes, whether they be related to warming OR cooling, with the priority placed on cooling since that leads to the most problems, as can be seen from history. ADAPTATION is the one and only thing human beings can do about “climate change,” since human beings aren’t in control of climate change and cannot stop it from occurring or alter it to out preferences.
As far as the science goes, we should be focused on understanding the natural drivers of climate, by identifying, observing, and measuring such forces, and by developing a sufficient understanding to reasonably predict any dramatic shifts so that we can prepare for them. All this tail chasing about CO2, which can be shown by the Earth’s climate history to be of absolutely no consequence to the Earth’s climate, is nothing more than a squandering of precious resources that could be used to solve ACTUAL problems.
Los Angeles Times shrill about an offshoot ‘horrors’ story which ‘would be caused’ by this same creature; Atmospheric rivers fueled by climate change could decimate wild oysters in San Francisco Bay
Study done by researchers at UC Davis’ Bodega Marine Laboratory and the San Francisco Bay National Estuarine Research Reserve.
That was naturally occurring, naturally; however, the next time it happens it going to be because of man-made climate change.
Calling Pres-elect Trump – put them on your list of where to cut funding.
The first hurdle they have to cross…
Is convincing Californians more rain is a bad thing
I keep telling people when they have a computer modeling program into which you enter accurate past data and get a result at odds to the actual past record their modeling program does not work. Some have twirled and twisted and prevaricated, others were honest and replied, “So, I get paid either way.”. Still friends with the honest ones.
And further, after they have “tuned” the models so that they CAN get a (known) result, that STILL does not mean their models have any predictive value. In order to have predictive value, the model must reflect an accurate and complete understanding of the forces that ACTUALLY drive the Earth’s climate. Since they haven’t scratched the surface of doing THAT (i.e., understanding the forces that actually drive the Earth’s climate), their models are nothing more than GIGO reflections of their hypothetical BS.
Actually what their “models” are is money generating scams. They don’t give a f**k about the environment or people, just stealing money from governments. The honest ones admit it, the liars, well, the liars have a personal profit and political agenda, in that order. Stripping the leftist ideologues of their power to funnel money to these liars will bring the entire edifice crashing down. Then REAL scientists can openly tell the truth. Then humanity can achieve progress.
Oh. I thought severe drought was the global warming fate for California.
Can you have a stormy drought?
http://realclimatescience.com/2017/01/california-aims-for-permanent-stupidity/
Stormy permanent drought from calif.
Isn’t global warming meant to be reducing the temperature differential between the tropics and the poles? And isn’t that temp differential the thing that drives such events?
Very confused. I need a climatology scientologist to explain it to me.
Of course you can have a stormy drought. Not to be pushing details, but from what I read, the idea is not more rain, just that whatever rain falls, will fall in intense storms.
Why not re-run this model for 1989-2015. Did they publish their code and data? Can it be independently reviewed? I’m holding my breath… Gasp.
Not with atmosgeric rivers in Calif.
atmospheric.
Fat fingers, little keys.
” should become more frequent ” …. it could happen, and hurricanes might become more frequent and stronger, snow could become a thing of the past ( still selling space on the lawn for those that want to experience this rare event.. I’m mystified that they’re not hordes of people) … ” it never rains in California ” there have never been mudslides or flooding ? Frequent or not, they are predicting/ projecting nothing. I can say with certainty that the midwest will experience drought again. How long or how severe ?
If it were true it is great news to us here in California. Even though we had more than average rainfall last year and so far this year, we are officially in a drought and must save as much water as possible. I myself have been saving rain water from my roof to be used later to water my garden. Mayby we will get enough to reestablish Lake Tulare as the largest lake in the lower 48 west of the Mississippi as it once was. Maybe the extreme weather will help with our population problem. Of course in trying to cut down on methane emmissions we need to rid the state of all organic matter including humans.
Climate policies will deal with your population problem. They will drive business and prosperity out of the state, and the (productive) people with it. Well, maybe that won’t deal so well with your population problem, since you’ll still have the unproductive ones. When everyone has a government job, you know you’re screwed.
California may get hit with an AR in the middle and south portion of the state, if this flow stays on course. This AR plume broke away 2 days ago, and started moving northeast…https://earth.nullschool.net/#current/wind/surface/level/overlay=total_precipitable_water/orthographic=-151.91,28.34,497
Good thing it is just an AR, an AK plume would be way worse! Ya know, .30 versus.223 and all.
Yet I was correct in my assessment of the flow as everyone can now see.
I read an article today that they are expecting a “river” of moisture to hit the southern California area late this week and early next week.
It was a local report but forgot where it was.
Here is one forecast showing the beginning of next week.
http://abc7.com/weather/southern-california-weather-forecast-tuesday/58983/
Mac
It is hitting Calif now.
Started yesterday
Maybe they are looking at this forecast.
http://woodland.ucsd.edu/images/gfs/images/ivt_USWC_latest_F150.png
Mac
You would think with the drought that this rain would be welcome. California has never gotten the rains like they do on the east coast or midwest. It’s always been feast or famine when it comes to water. Some of the reservoirs will fill up.
No one receiving goberment funds was harmed by publishing this fiasco.
…and many in the propaganda press strongly “believe”.
We must remember, MIT manufactured the building 7 collapse model. The Moloch Institute of Terror and Contrived Science also has connections to MITRE.ORG and other fine institutions of which are connected to our manufactured reality.
“… MIT scientists have found that such extreme precipitation events in California should become more frequent as the Earth’s climate warms over this century.”
“Found” is the wrong verb here.
Yes, the found exactly zero. The took a well funded WAG.
So the experts at MIT, with their ‘actionable’ hypotheses, think we ought to do what? What action? A link to the 1996/97 ARK storm mentioned in comments above is illuminating. http://cepsym.org/Sympro1997/roos.pdf The illumination comes in the form of ‘Should we or should we not build the Auburn Dam’. There is no other discussion. The storm dropped as much as 42 inches of rain in nine days above Oroville Dam with a peak inflow of 330,000 cubic feet per second and the system worked to mitigate downstream damage.
We get one of these storms every few years. Not to the degree of the 1986 or 1996 or 1955 or 1969 or 1909 or 1862 storms, but we get them. Now these folks are claiming we will get 2 – 3 more such storms every year? Nonsense. We don’t even average on per year now. They are actually saying that storms we now see on a multiyear scale will occur multiple times per year?
Once again it looks like models…all the way down!
pbh
When are people going to get it? It is cooling which causes severe weather. Warming is a pleasant walk in the park. GK
Yup – people should be thankful we’re fortunate enough to be living in a warm climate, relatively speaking. And if they don’t believe that, they need to do some historical research about how marvelous life was for humanity during the Little Ice Age.
Well. If their analysis is true it is time to raise the elevation on Shasta Dam and build more storage reservoirs, even if they are off stream. Also need to provide more wells to replenish ground water systems. All the previous global warming scenarios suggested more droughts.