Study: Jet stream induced weather will remain normal and predictable – despite ‘climate change’

Weather should remain predictable despite climate change

Simulations of jet stream behavior in a warming climate suggest ranges of forecasts in the mid-century will be similar to those in present day, MU study finds

COLUMBIA, Mo. – According to the Intergovernmental Panel on Climate Change, temperatures are expected to rise between 2.5 and 10 degrees Fahrenheit over the next century. This warming is expected to contribute to rising sea levels and the melting of glaciers and permafrost, as well as other climate-related effects. Now, research from the University of Missouri suggests that even as rising carbon dioxide levels in the atmosphere drive the climate toward warmer temperatures, the weather will remain predictable.

“The jet stream changes character every 10 to 12 days, and we use this pattern to predict the weather,” said Anthony Lupo, professor of atmospheric science in MU’s School of Natural Resources, which is located in the College of Agriculture, Food and Natural Resources. “We were curious about how this would change in a world with higher carbon dioxide levels. We found that in that warmer world, the variability of the jet stream remained the same.”

Lupo and Andrew Jensen, who earned his doctorate at MU, used an existing climate model to simulate jet stream flow in the Northern Hemisphere. The simulation monitored a variable that responds to jet stream flow changes and can indicate global-scale weather instability. Researchers used this variable to determine when the jet stream altered its flow. Since meteorologists can only accurately predict weather within the 10 to 12 days between jet stream flow changes, a shift in this time frame would directly impact weather predictability.

Over the course of a simulated 31 years, their observations indicated the jet stream would change its character about 30 to 35 times per year, a number that is consistent with current jet stream patterns. As the time frame used to predict weather did not change, the researchers concluded that weather would likely remain as predictable in a warmer world as it is today. The results do not address the effects of climate change on the nature or frequency of weather events but instead focus on the range of predictability afforded by the jet stream. In addition, the researchers did not extend the simulation past the mid-century to ensure their data was as accurate as possible.

“Climate change will continue to create a lot of ripple effects, but this experiment provides evidence that the range of forecasting will remain the same,” Lupo said.


The study, “The Dynamic Character of Northern Hemisphere Flow Regimes in a Near-Term Climate Change Projection,” was published in Atmosphere. (open access)


The dynamic character of an enstrophy-based diagnostic, previously used in the study of atmospheric blocking, is examined here, in near-term future simulations from the Institut Pierre Simon Laplace Climate Model version 4 (IPSL-CM4) and version 5 (IPSL-CM5) climate models of the Northern Hemisphere flow for moderate climate change scenarios. Previous research has shown that integrated regional enstrophy (IE) increases during blocking onset and decay, which is a reflection of planetary-scale instability. In addition, IE has been shown previously to increase during flow regime transitions in general, even those not associated with blocking events. Here, a 31-year IE diagnostic time series is examined for changes in short term (5–40 days) planetary-scale variability that may correspond flow regime changes in an increased carbon dioxide environment. The time-series analysis herein indicates that the IE diagnostic provides evidence for approximately 30–35 atmospheric flow regime transitions per year in a warmer climate, which is similar to that of the control run and the latest 30-year observed climate, as derived from re-analyses. This result has implications regarding the predictability of weather in a warmer world.


46 thoughts on “Study: Jet stream induced weather will remain normal and predictable – despite ‘climate change’

  1. If the global temperature rises or decreases by as much as ten degrees, I would say that all bets are off. Can anyone tell me what the jet stream was doing during the last glaciation? If Dr. Mann can speculate that the Atlantic Conveyor is going to stop, why would we assume that the jet stream couldn’t also change.

    On the other hand, it is extremely likely that weather forecasts will continue to enjoy their present accuracy.

      • Yes indeed, he did. Trees do that, stopping water flow. There are precedents, like this one:
        Vol. LII. JULY, 1901 . No. 3.
        (tiniest bit of \sarc)

    • Temps are in fact going to drop 10C over the next 90K years. It’s the only reliable prediction you can make about the climate.

    • The weathermen can rest easy . Their jobs will be safe. About the PhD Atmospheric ‘scientists’ on the other hand ; all hell will break loose on them when the hoax is finally accepted by the media.

      • The press won’t “accept” that they were wrong about global warming. They will just forget that they ever said it was a problem. In that vein, they forgot about the ‘global cooling’ panic of the 1970s that they once permoted. “Nevah happened.”
        What will happen is that slowly the acolytes of the Church of CAGW will slowly slip out the back door when no one is looking. The cathedral will stand empty with a lot of guilty-looking people claiming “Not me! I NEVER believed in global warming.” :)

    • Bob, IMHO, In an ice age, it stands to reason that the bulk of equatorial heating is shed to the north and south poles via a much faster jet stream as it has a much shorter distance to travel to temperate zones where it is radiated to space. Hence a much more active and stormy weather planet for the majority of the ice house condition. Intense weather and a lot of storms. Lots of other variables at work too, but the Atlantic Gulf Stream would have shifted southerly into Southern Europe and Northern Africa along with the jet stream. Hence the Sahara region was much wetter as evidence shows it was a much wetter place just 9000 years ago when the northern NA and European continental glaciers were finishing melting.

      A warming world should have an opposite effect where the temperature gradient between the equatorial regions and the warming poles has a much lower tempature gradient overall and a much slower and longer jet stream, which are a function of ocean circulation currents that are further north/south while the planet continuously sheds heat off to space on heats circulatory journey poleward.

      Am missing 9 volumes of other information in this condensation of ocean current and jet stream conditions in a cold vs. warm planet, but the warmista’s must have it backwards in predicting a much more active weather planet in a warming world. A colder (glaciated) world is a constant brutal stormy weather planet so embrace the warmth while it lasts. We all wouldn’t be here if not for the extra warmth of the last 200 years and utilization of fossil fuels.

      • I agree. It seems southern Alaska and the west coast of Canada don’t glaciate because the warm Pacific air carrying the moisture for the large glacier over the rest of Canada and the northern US kept those coasts clear of ice.

    • This post reads:
      “According to the Intergovernmental Panel on Climate Change, temperatures are expected to rise between 2.5 and 10 degrees Fahrenheit over the next century.”

      This IPCC-predicted temperature rise of 2.5 to 10 degrees Fahrenheit over the next century is based on an ASSUMED climate sensitivity to increasing atmospheric CO2 that is at least an order of magnitude (10x) higher than reality – it is unscientific scare-mongering nonsense.

      Academics who believe this false alarmist nonsense live in a virtual world, where their baseless models trump actual observations. There is NO credible evidence that climate sensitivity is this high, and ample evidence that it is not.

      Even assuming (for the sake of argument) that ALL recent atmospheric warming was caused by increasing atmospheric CO2 only results in a Transient Climate Sensitivity of ~1C/(2xCO2), which will NOT cause dangerous global warming. The reality will be less than that, because it is clear that natural variation plays a large role in weather and climate.

      Natural variation, the null hypothesis. explains climate well enough.

      To prove that humanmade global warming is significant, one has to disprove the null hypothesis, and the global warming alarmists have failed to do so. All they have done is to bully and harass those who point out their glaring falsehoods, spouting specious nonsense like “the science is settled”.

      Before the advent of fossil fuels, climate was warmer AND colder, weather was gentler AND wilder, CO2 was higher AND lower, etc., etc..

      Global warming alarmism is a costly, destructive fantasy that is promoted by scoundrels and embraced by imbeciles.

      As we published wit confidence in 2002:
      “Climate science does not support the theory of catastrophic human-made global warming – the alleged warming crisis does not exist.”

      Regards to all, Allan :-)

  2. Well this is inconvenient. Disturbs the Legend of the Polar Vortex.

    On the other hand, it could be very convenient. If the ‘weather’ patterns don’t change enough for the little people to notice that doesn’t mean that the IPCC experts won’t still be able to ‘see’ The Warming/Bad Climate Change/Climate Disruption/Climate Triggering/Gaia Mad.

    So the Emperor can still have clothes after all no matter what happens.

  3. Hmmm.. the leap from higher CO@ to higher temperatures taken as a priori.
    But daily weather will still be predictable, to about the same accuracy as today’s predictions? Very low hurdle indeed.
    Perhaps these will remain in the category of “news likely to be true”.

  4. I think these researchers are about to be targeted for “re-education” because their story just isn’t alarming enough.

  5. I predict that actual Weather Forecasting 10 to 12 days out will remain as reliable as they are today. They may even improve. (Though weather forecasting hype at TWC will become more strident.)
    Climate Model Forecasting, on the other hand, will remain as dismal 10, 20, 30, … 100 years out as Hansen’s was 30 years ago.

  6. The image caption that ‘weather forecasts will remain reliable’ is dubious, since they aren’t. Perhaps what was meant was, ‘will remain as unreliable as today, not worse’.

  7. “temperatures are expected to rise between 2.5 and 10 degrees Fahrenheit”
    “used an existing climate model to simulate jet stream flow ”
    “weather would likely remain as predictable in a warmer world as it is today. ”


  8. They simulated a 31-year period in the future with computer models. Pardon me if I place little faith in that process… which can’t be proven or disproven for many, many years. It’s the same with temperature models based on CO2 levels.

  9. What will be interesting is whether quantum computers in the next 10 or 20 years will be able to improve weather forecasting accuracy.

  10. Whoo Boy!
    This modeling adventure stretches the last remnants of credibility past the tipping…….breaking point.

  11. Prior to one of the coldest winters in US history occurring, it was well understood that this year’s La Nina event would cause the Jet Stream to shift from going straight over the US West Coast, to shifting Northward over the Arctic and bringing bitterly cold winds and snow down to Central and Northeast US states, and that is precisely what happened…

    All Leftist CAGW advocates could do was to blame the bitterly cold and harsh winter on Global Warming, by dusting off Ye Ol’ “Global Warming is causing Global Cooling via the Polar Vortex phenomenon” meme…

    Sure, for ignorant Leftist CAGW acolytes, Ye Ol’ “Global Warming is causing Global Cooling” made perfect sense, but the rest of the rational world collectively suffered severe eye cramps from constantly rolling their eyes at all the Leftist foolishness…

    Since the current La Nina pattern is about finished, ENSO will soon enter a neutral cycle, which will bring milder/average winter temps/snow for the next couple of years, before another El Nino event occurs, which will bring a warmer winter season for the CAGW advocates to exploit saying, “See, CO2 is causing milder winters!”…..

    I predict more severe eye-cramps over the next 3~4 years, as ENSO goes through its natural cycles and Leftists continue to laughably confuse weather with climate…(which Leftists always accuse rational adults of doing….)

  12. Wait: “Predictions were changed to “Projections” since the predictions were all wrong. Now “the weather will remain predictable” Now they are projecting that the weather will remain predictable?

  13. As an exercise in weather ‘predictability’ I once tracked weather forecasts that called for weather changes –
    anything other than substantially ‘tomorrow’s weather should be just like today’s’. Over 50% of the forecasts for changing weather had to be amended significantly (change of more than 5° F in temperature, more than 25% in anticipated precipitation, or more than 12 hours in the arrival time of a ‘front’) between their initial report and the development of the actual event, typically about a week.

  14. It’s good to hear that, despite all of its other magical properties, CO2 won’t affect the jet stream. Whew! That’s a relief.

  15. This caught my eye: “meteorologists can only accurately predict weather within the 10 to 12 days between jet stream flow changes”. I think that’s being rather generous.

    I record the daily readings from the weather service’s local station, but when it says “sunny, clear” and I look out the window and see clouds, or it says “rain” and it’s snowing, I have my doubts about their ability to predict the next 10 minutes of weather.

    I know that those people don’t go outdoors if they don’t have to, but I figure that if I’m patient enough, eventually, the weather guessers will get things semi-right.

  16. Hmmm. El Niño pattern normal. La Niña pattern normal. Gulf steam normal. Jet stream normal. Arctic Oscillation pattern normal. And liberals are tearing their hair out, knashing their teeth, rendering their clothes, flagellating themselves, wearing sack cloth, sitting in ashes, and screaming their distraughtness over less than a degree of warming. Okey dokey!

  17. As you were folks with the unpredictable extreme weather meme and stand by for our updates and predictions on inclement weather. Oh and we’ll need more grants for those.

  18. So CO2 does not significantly, if at all, affect the major weather pattern setting process of the temperate regions of the world – the jet-stream It is well known that the jet-stream is greatly affected by solar events (there are many references, here’s one ). Also the jet-stream is especially in the important weather determinant in temperate regions of the world — a MAJOR player in setting weather patterns, as it greatly influences the paths of high and low pressures (convection effects) around the globe, and thus dictates where the precipitation is likely to fall.
    So this solar affected weather process GREATLY affects the weather. And climate is judged to be the aggregation of the weather over a 30 year period (by the IPCC). Therefore the variation in the jet-stream must be a major climate determinant.

    So if CO2 doesn’t affect this major process how can it affect the climate to any great degree?

  19. In the real world that these types don’t seem to inhabit, the jetstream has already changed from zonal to meridional over the last few years leading to wild meanders north and south.

    I believe the march of computer models has made forecasting worse by removing the human experience from the forecasts. The changed jetstream only makes that worse since it was admitted live on air during a BBC weather forecast that their models don’t work with a meridional jetstream.

  20. You know they DID run their models out to 2100. A unavoidable need to satisfy their professional, if not ideoligical, curiosity.

    The lack of comment on the results of the longer run suggests two reasons, both negative from the CAGW perspective:

    1. No changes resulted. Therefore, high CO2 doesn’t materially change atmospheric conditions. Stability in one major area suggests stability in others.

    2. Bizarre changes resulted. Changes that are simply not believable with long term evidence. Therefore, there are serious errors in the models which build on themselves and become obvious over the 50+ year period. Shorter term periods have a built-in, progressive but unknown failure to respect reality. More uncertainty than they wish admitted.

    Non-responses are also responses.

Comments are closed.