Unravelling the uncertainties of predicting future heatwaves

Sep 30, 2011

(PhysOrg.com) -- As the UK swelters in the grip of a late September heat-wave researchers at The University of Nottingham have warned that while Indian summers could become more common, heat-waves in the future could become even hotter. Moreover, they could have important implications for human health.

However, their research suggests that we are going to have to take a lot more notice of the things we don’t understand about the climate. In other words, we have up until now, been underestimating the uncertainties of .

Dr Simon Gosling, in the School of Geography, said: “It is important that we represent this uncertainty when we try to understand future climate change. One way of understanding how heat-related mortality risk will change in the future is through the application of numerical models that simulate the effects of climate change on . Up until recently such models have typically produced projections of climate change impacts based upon only one or two possible future climates. However, great uncertainty is associated with the numerical models that simulate future climate, due in part to the limited understanding of the physical climate system. This means that this climate modelling uncertainty is often considerably under-estimated. A more complete treatment of this uncertainty is important for better informing risk-based decision-making.”

Using a technique called Perturbed Physics Ensemble (PPE) – Dr Gosling, in collaboration with experts from The University of Auckland and The Met Office Hadley Centre, ran 17 slightly different versions of a complex climate model to explore what the future climate might look like, and what it might mean for human health. The study, published in the journal Climatic Change provides the most complete treatment of climate modelling uncertainty in climate change health impacts assessment to date.

Dr Gosling said: “The European heat wave of 2003 had a devastating effect on human health. The extremely high temperatures have been estimated to have caused over 35,000 deaths across the continent. Climate change predictions indicate that events such as this heat wave could occur more often in the future and that future heat waves could be even more extreme. Moreover, there is evidence that towards the end of this century, every summer in Europe could be as hot as the summer of 2003. Given the scale of the effects of the 2003 , and the predictions of more frequent and intense heat waves due to climate change, there is a need to understand how these kinds of events may affect human health in the future. Most importantly, we need to know how certain we can be about these predictions.”

By considering the different patterns of climate change projected by 17 climate models, the study gives an indication of the current level of scientific confidence in projected changes in heat-related mortality for six cities; Boston, Budapest, Dallas, Lisbon, London and Sydney. The cities were selected to represent a range of different climates.

Dr Gosling said: "Climate models include complex equations about how the climate works. For example, there are mathematical equations that describe how the sun's radiation reaches the land surface, there are equations that describe how the oceans currents move. Each version of the model used in a PPE is different in terms of the equations the model uses to work things out about the future climate.

“For example, the way that clouds are represented or the way water evaporates from the earth's surface. This is important, because we just don't understand everything about how the climate system works. For instance, we still do not completely understand the role of clouds in affecting climate change. As such, we are uncertain about certain aspects of the climate system. Essentially, we don't understand all the physics of the .”

Dr Gosling’s research demonstrates that relying on a single climate model for estimating future health impacts is not appropriate. The main finding is that although there is a lot of uncertainty, it is very likely that heat-waves could become hotter in the future in London and that heat-related mortality could increase six-fold. This is also true for Boston, Budapest, Dallas, Lisbon, and Sydney. However, Dr Gosling does note that it is possible that humans will acclimatise to warmer temperatures in the future. “The question is, by how much”, he added, “since we have little observational evidence to indicate how much humans can actually acclimatise to hotter and more frequent heat waves”.

Explore further: German scientist starts four-week swim down Rhine river

More information: The paper can be found at: www.springerlink.com/content/60120mg13721j222/

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User comments : 12

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omatranter
3.7 / 5 (3) Sep 30, 2011
The Illuminati, by causing global warming to depopulate the planet, while simultaneously promoting the deniers agenda through their stooge Rupert Murdoch are truly playing the long game. They await the "coup d'état" of a Frozen Earth to finish off all of those who adapted to fiction of Climate Changes truth while they are safe in their geothermally heated Icelandic (The global economic crisis barely affected the Icelanders because they spurned the calls for austerity, proving their worth to the Illuminated) bunkers listening to the Vienna Philharmonic.

I am on to their game, and they know I am on to their game, and they know I know I am on to their game... whooa I feel giddy, their mind control devices must have pinpointed my location again.

Mark my words "Repulsive Neutrons"
omatumr
1.5 / 5 (8) Sep 30, 2011
Big Brother is running scared today.

Yesterday the German journalist the German, Quirin Schiermeier, was allowed to publish WikiLeaks "news" in Nature magazine that UNs Clean Development Mechanism (CDM) is but a fig leaf for wealth transfers from industrialized nations to poor developing nations:

www.powerlineblog...arce.php

www.nature.com/ne...20110929

This seems to be a complete reversal of policy at Nature magazine, which banned me from posting comments on reports published there after I publicly called for the resignation of the editor, Dr. Philip Campbell, for publishing misinformation about the influence of Earth's heat source - the Sun - on Earth's changing climate.

Dr. Campbell and NPG were sent copies of this note for their response.

With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
http://myprofile....anuelo09
jsdarkdestruction
3.3 / 5 (7) Oct 01, 2011
you were banned because you spammed nonsense conspiracy theories like this one you are pushing now oliver. that article featured 2 points of veiw and didnt prove anything.
MarkyMark
5 / 5 (2) Oct 01, 2011
you were banned because you spammed nonsense conspiracy theories like this one you are pushing now oliver. that article featured 2 points of veiw and didnt prove anything.

He is pretty shameless really and doesant care if he spouts nonsense like his Neutrino Repulsion nonsnce or the fact that he was a former Appollo investigator while failing to stat the reaon he was dsmisssed frm that post, probably a mixture of his rathe skey grasp of science and the fact he kept on flashing photo of his naked daughte befor ad after being made into a real oan by him.
jsdarkdestruction
1 / 5 (2) Oct 02, 2011
neutron repulsion actually, he does claim neutrinos do not change flavor though.....
kaasinees
3.4 / 5 (5) Oct 02, 2011
The heat waves were cause by solar flares... Solar activity was high this week, there was an X class solar flare... But i see it nowhere mentioned in this article. SDO, if you do not believe me.
kaasinees
4 / 5 (4) Oct 02, 2011
@jsdarkdestruction.

Any reason for rating me a 1?

Look up SDO and SOHO data and they will confirm Xclass flares this week and a few weeks ago. Of course this is the source of the heat waves?

youtu.be/rlHIoRxj_nU
jsdarkdestruction
1 / 5 (1) Oct 02, 2011
I cant find that video on youtube, its telling me it cant find it.
No, not "of course", ive seen no reason to believe that. I've read about recent solar flares. their were also x class flares in febuary and in march. their being x class flares proves nothing about them effecting earth, as long as the cme's dont hit us square on the effect is minimal. You didnt deserve a 1 i guess, you did have some thought behind it. i figured you were one of olivers friends who come on and spout nonsense.
kaasinees
4 / 5 (4) Oct 02, 2011
I am talking about X class flares that were predicted to hit earth.

But it also proves that solar activity is high at the moment and is mostly responsible for the heat waves.
jsdarkdestruction
1 / 5 (1) Oct 02, 2011
they didnt hit the earth though......at best it was a glancing blow. not enough to "cause heatwaves".
kaasinees
4 / 5 (4) Oct 02, 2011
@jsdarkdestruction, here you go.

http://www.nasa.g...302.html
jsdarkdestruction
1 / 5 (1) Oct 02, 2011
i still dont see where it says x class solar flares effect earths climate and are the cause of past heat waves.