Recycled science: Reflective surfaces alleviate heatwaves

From ETH ZURICH and the “obvious science” department comes this study that is little more than a recycle of what is already understood about crops and “shininess”, back in 2009 – reflective surfaces absorb less heat during the daytime. Just wait till the greens deal with GMO engineered “reflective corn”, they’ll have a head-exploding dilemma.

Climate change will make heatwaves more common, and continental areas and urban regions that become significantly warmer in summer will be particularly affected. Together with colleagues from Australia and the US, ETH researchers have now detailed a practical approach that combines clever land use and urban radiation management to help cool extreme summer temperatures locally. Their study has just been published in the journal Nature Geoscience.

Greater reflection breaks up temperature peaks

The scientists’ approach is based on the different reflection properties of ground surfaces. For instance fields left unploughed after harvest reflect significantly more sunlight that ploughed ones (as ETH News reported). Similarly, crop selection for brighter species and the implementation of reflective material on roofs, streets and other urban infrastructure could increase the surface reflectivity and cool local climate .

“These measures could help to lower extreme temperatures in agricultural regions and densely populated areas by up two to three degrees Celsius,” says Sonia Seneviratne, ETH Professor of Land-Climate Dynamics and first author of the study. In this context, the hotter it becomes, the stronger the effect. The cooling effect only works in the short term, however, and is local or regional rather than global – but this regional contribution is still very important, emphasises Seneviratne.

Suitable for Europe and the US, less so for Asia

The researchers obtained their findings using simulations. They used these simulations to examine how radiation-optimised agricultural surfaces and metropolitan areas in North America, Europe and Asia affect average temperatures, extreme temperatures and precipitation.

The models showed that the measures had a negligible effect on average temperatures and only slightly altered precipitation – except in Asia – but significantly reduced extreme temperatures. In Asia, India and China, the levels of the crucial monsoon rains also decreased in the simulations, suggesting that the selected approach is unsuitable for these countries.

Alternatives for climate and geoengineering

The measures that could be used for this type of radiation management already exist and have largely been tested, although they have only been applied on a small scale or for other purposes. In contrast, it is doubtful whether other climate techniques currently discussed as “geoengineering” actually work to adjust or avoid climate change. Interventions such as spraying sulphate aerosols into the atmosphere, fertilising the oceans with iron or placing huge mirrors in space are likely to have unpredictable effects on the Earth’s climate and ecosystems, potentially making the situation even worse.

“Regional radiation management can be effective, but even here, we have to consider any potential effects on food production, biodiversity, CO2 absorption, recreation areas and much more before we can actually implement it,” says Seneviratne. And she points out: “Even this climate technique is no silver bullet; it’s just one potential tool among several others in the battle against climate change.”



Seneviratne SI, Phipps SJ, Pitman AJ, Hirsch AL, Davin EL, Donat MG, Hirschi M, Lenton A, Wilhelm M, Kravitz B: Land radiative management as contributor to regional-scale climate adaptation and mitigation. Nature Geoscience, 29 January 2017, doi: 10.1038/s41561-017-0057-5


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It’s just more junk science. Stop the funding.

Pop Piasa

Definitely! The whole study is based upon this assumption:

Climate change will make heatwaves more common…

When will this actually happen?
This is more a statement of belief in the Church of Omnipotent Greenhouse in Carbon than it is a scientific paper.

Thomas Ryan

Climate change will make heatwaves more common,
Well doesn’t this mean that the “climate” can change to colder as well?
A have your cake and eat too argument.

Peter Morris

Haha! SimEarth told them it was so.

Keith J

What do photovoltaic panels do to albedo?


Photovoltaic panels warm the earth as they are specifically designed to lower Albedo and thus trap energy to be eventually used as electricity.
If you want to warm the earth then plaster it with solar panels. If you want to cool it then paint everything white. The Stephen-Boltzmann equation says so.


Reflective corn is more intelligent and less reactive than ordinary corn.

Alan Robertson

Does that apply to bald guys?

Pop Piasa

Would redheads reflect more infrared than white haired old folks? Maybe that’s a factor in UHI effects.

Bryan A

Let me reflect on that for a while

Pop Piasa

Such reflective corn that it’s become philosophical corn. Just like my humor.


10 thumbs up for that pun.


There are 10 kinds of people, those who understand binary, and those who don’t.

Bryan A

I hope you don’t mind if I borrow that one once in a while


We should be thanking our lucky stars that the geoengineering lobby can now focus on reflective farm crops rather than something that could actually be damaging to the environment.

On reflection it seems a good idea!

Tom in Florida

Reminded me of an old song. Not all that relevant but soulful with nice added video. Sometimes it’s OK to get nostalgic.
Reflections of My Life by Marmalade

Tom in Florida


Thanks — I like that oldie. Classic late 60s sound.


“by up two to three degrees Celsius”…fine….global warming solved…next

So maybe white floating plastic discs to disperse over the ocean? Or do micro particles of plastic already do that? Except they are not white.
Maybe a roll up mat of white mesh that is say 30% open, to allow sealife underneath, but reflect from 70% of the area. Then in winter-cool weather could roll it up like a window shade to allow optimal winter temperature. The options are endless; as is the nonsense..

Ron Long

Right On! That’s what I said in my prior Watts post “Key Words: Geologist, Beer, Pizza” wherein I recounted the event where a hermit cooked a pizza on a black basalt boulder. Sure those pyroclastic volcanoes make a lot of noise and get the headlines, but if you want to heat things up get yourself some flood basalts. What’s that? You want to cool things down? Sorry.

J Mac

On further reflection, perhaps we should address real problems, rather than fear based nonscience. That would be cool…..

Dr. Bob

I spent many years working with the Commercial Aviation Alternative Fuels Initiative (CAAFI, an FAA/Airline sponsored activity) on different fuel production pathways and their impacts on GHG emissions. Everyone believed that energy crops were the only way to produce low GHG emitting fuels for airline use. That is until an MIT professor included albedo change for the land as it was (prairie) versus if used to grow energy crops. The change in albedo (reflectivity) was significant enough to negate the benefit of alternative fuels produced from things like switchgrass.
There are a great many other problems with growing energy crops for jet fuel production which can be part of many further discussions.
Suffice it to say, the whole CAGW area is in its infancy and so much is not known about this area including the prospect that it is totally meaningless or at least a trivial matter not worthy of the grand effort being expended on it.

According to this:
aviation is responsible for 2% of man made emissions, expected to rise to 3% by 2050. As I comment there – hardly seems worthwhile doing anything about it, there are easier ways to reduce aviation emissions and clearly nobody in power believes the extra CO2 is a problem as there isn’t an urgent world wide effort to generate all of electricity by nuclear. You also see on display there the lack of logical thinking by people who
ignorantly believe the climate charlatans.


They used models, which is flakey. They could have collected real data. There are meteorologists that have noted a reduction in the number of very hot days in Iowa and have associated that change with the increase in corn planting density.

Komrade Kuma

“Just wait till the greens deal with GMO engineered “reflective corn”, they’ll have a head-exploding dilemma.”
No dilemma at all to the hive mind of the Green Blob. “GMO engineered “reflective corn”” = GMO ergo no dilemma. ‘GMO HAS GOT TO GO’ etc. “Reflective corn that is GMO engineered” might confuse them for a while I suppose but a quick rephrasing will solve that for the hive mind.

Michael Jankowski

I expect we’ll see a study claiming non-GMO corn is more reflective than GMO corn.

Pop Piasa

…probably is, after you treat your field with glyphosate… ;-0


I don’t really see a problem with seeding the oceans with iron, but not for the purported reasons. Considering we’re overfishing virtually all fish stocks, beginning at the bottom of the food chain with increasing phytoplankton mass would only lead to positives in corresponding zooplankton, copepod, mollusk, small-, medium- and large-sized fish populations.
Screw the non-issue of climate mitigation and do it for improving the health of the oceans. We’ve seen it before, both by natural volcanic fertilization as well as human experimentation, and all without negative consequence.

Keith J

Dr Martin’s hypothesis was the iron would stay at the surface. He didn’t know of vertical migration which meant herbivory at night and the grazers heading to the depths before sunrise. Digestion at depth meant the iron seeding had much greater loss than normal sedimentation rate. Iron seeding doesn’t persist. Neither does carbon dioxide seeding. Eutrophication requires specific conditions as nature is a complex system of negative Feedbacks.

Mihaly Malzenicky

Unfortunately, we can sleep for a long time, but we will soon be forced to accept the chemtrails idea even if it is effective. Not everyone will like it for sure.


Has anyone noticed that we are travelling through space, revolving around the sun, which in turn is revolving around the centre of the Milkyway, which is hurtling through the Universe? That in our eliptical orbit around the Sun we are at the closest to the Sun, which will now get greater. Maybe that has something to do with the heat here down under?


Now you can save the world and look fashionable.comment image

Old Man Winter

RW- I think you may have just solved a
climate mystery- the cause of the pause.
Could it have been more warmunistas wearing
tin foil hats reflecting solar energy
back into space? 😉
It could also explain what happened to
Trenberth’s missing heat! 😉

This is especially effective with a vacuum beneath the hat. Should do well in California.

Svend Ferdinandsen

Only local effect. Yes but heatwaves are also very local.
Is the study polical correct, because it makes it harder for dark skinned peoble to achieve the same effect 🙂

Mark B.

Vacuums IMplode.

John F. Hultquist

“>em>In Asia, India and China, the levels of the crucial monsoon rains also decreased in the simulations, . . .”
Just a guess, but it sounds like they are using the 1950’s textbook explanation.of monsoon mechanisms. Their simulations show effects being local and regional. Asian monsoons involve significant high altitude flows within the atmosphere.
Once an Asian monsoon gets set up, the reflectivity of the surface is of no concern, either.
A “reflective” crop needs to grow some before it becomes reflective. Do they want to spray-paint a field white as they plant the corn?

Geoff Sherrington

These experts should be in Melbourne during a typical heat wave. Moderately strong winds from the hot, dry deserts to the North come sweeping down, making the temperature rise with scarce regard to whatever crops might be in its path. It simply overwhelms. Good luck to people like co-author Andy Pitman who have poor understanding of the relative magnitude of natural and man made events. Dreamin’. Geoff.

Geoff Sherrington

Also, official BOM temperatures for Sydney, Melbourne, Adelaide and Hobart do NOT show an overall increase in heat waves, not frequency, not severity, not duration. There s no climate change/ heat wave effect showing in the BOM temperature data for these capitals over the last 100 years or more. The BOM refuses to discuss this lack of heat waves with me. They prefer to promote imaginary increases. Geoff

If you spread a molecule thick oil film over a water surface it will lower the albedo. Israeli scientists used this to warm ponds — maybe for aquaculture. It probably occurs naturally — biology and seeps — and certainly we are spilling millions of gallons of oil each year. AGW, but not the sort anyone is looking at.
Oil smoothed oceans also produce fewer aerosols = fewer clouds = more warming.
Prediction: enclosed bodies of water subject to oil pollution will warm more than global trends.


It will also warm your swimming pool. However, the stated action here is that the film will reduce evaporation and the cooling that comes with it. Would be happy to get a couple of months extension at each end of the swimming period, and even better to have the pool warm an extra few degrees.
Trouble here is that every time I try this remedy (with commercial product) it pours with rain, pool overflows and the protective molecule thick blanket disappears down the drain.

I didn’t know that. Thank you. I’ve seen a little bay in Ibiza being smoothed by just the sun oil used by the bathers, and I’ve seen the Atlantic smoothed from abeam Portugal nearly all the way to Madeira by heaven knows what — if it wasn’t coming up from the sea bed it must have been an unexpectedly persistent something.
It’s not just albedo, there are fewer breaking waves which means less low level cloud. I keep nagging Willis to look a the numbers as it’s beyond my ability, but no luck so far.


As always, climate science redefines already well defined terms in order to scare up more money.
A heat wave is defined as a departure from average for that location at that time of year.
If global warming does manage to heat the planet noticeably, it will heat the average. As a result, it will take the same number of degrees warming from the average to create a heat wave.
Heat waves will not be any more common.
In the summer, 90F in the afternoon is a heat wave in New England. 90F is a normal morning in Miami.

More computer games. Besides, very tricky to GMO better reflective corn. Photosynthetic chlorophyll absorbs and uses blue and red light frequencies. It already reflects unabsorbed green—which is why leaves, including corn leaves, we see as green. Remember that unlike paint pigments, any visible color can be made by mixing red, green, and blue light frequencies. That is why all computer, portable electronic, and TV screens are known as RGB screens. Their subpixels produce R, G, and B. By chandingnthe emissive intensity of each subpixel at each frame, we get the technological miracle most use without any underlying comprehension of the basic physics. Including the numpties who wrote this nothingburger nonsense paper. Duh oh!

Juan Slayton

Hi ristvan,
Been puzzling about this spectrum business myself. Chlorpphyll reflecting green is a no brainer. But I’m not sure about how much and what part of the rest of the spectrum is actually used. Just because it isn’t reflected doesn’t mean it contributes to photosynthesis; it might just be absorbed to produce heat. I throw this out in the expectation that someone here knows something about this…

John F. Hultquist
Juan Slayton

Thanks, John. Very informative article, and as usual, nature is more intricate than expected. Very interesting that my assumption about discarding green light is incorrect:
Typical absorption values of green light (550 nm) range from 50% in lettuce to 90% in evergreen broadleaf trees. As observed above in the action spectra, the entire light spectrum is used to drive photosynthesis. It appears as though green light is not a safe light and that green light is required for optimum whole plant photosynthesis.

Yes this is a bleedin’ obvious study, but then, it is only recently that my local authority stopped invoking the Bluff Act, by discouraging reflective paints and surfaces so the fat-cats up the hills didn’t suffer effects that compromised their over-priced views. (It may have been the threat of judicial review on the grounds of blatant disregard of federal law that brought about the change.)

Joel Snider

As I remember, this was used as a basis for the suggestion to paint all our freeways bright white – as in blinding white.
I’m sure this would reduce our human footprint and remove a few drivers from the road – via a dramatic uptick in fatal crashes.
Of course, the approach here in the Northwest is to simply congest traffic and toll roads so highly that commuters can’t afford to drive on them.


The planet ain’t broke. Quite trying to fix it.

Bryan A

GMO a tree with clear chlorophyll this will give it white leaves and greatly increase it’s reflectiveness

John F. Hultquist

You can start with white fruit and work on getting the leaves to match:comment image

4 Eyes

“Climate change will make heatwaves more common” Prove it. I’ll be generous – explain why, No maths, no experiments required just a scientific explanation.

Mihaly Malzenicky

Thank you very much for generosity, but you do not need any proof, you have enough probability of one percent, since when the process starts you can not stop and soon you will find yourself in Venus.

Bryan A

Atmospheric conditions on Venos will NEVER happen on Earth. Most of Venus’ stifling heat isn’t a direct result of CO2-greenhouse effect. Venus isn’t even significantly warmer than earth due to it’s proxcimity to the sun. Venus is far warmer because of Atmospheric Pressure 90 times denser than Earth’s atmosphere.

Rick Lafford

I found it interesting that the authors start with a hot day, which I believe is weather, but then jump off to making a statement about climate.