From the NORWEGIAN UNIVERSITY OF SCIENCE AND TECHNOLOGY and the “playing with climate models for doom outcomes is too stupid to be science” department.
Envisioning a future where all the trees in Europe disappear
Using climate models to take a deeper look at the regional effects of global warming
Vegetation plays an important role in shaping local climate: just think of the cool shade provided by a forest or the grinding heat of the open desert.
But what happens when widespread changes, caused by or in response to global warming, take place across larger areas? Global climate models allow researchers to play out these kinds of thought experiments. The answers that result can serve as a warning or a guide to help policymakers make future land use decisions.
With this as a backdrop, a team of researchers from the Norwegian University of Science and Technology and Justus-Liebig University Giessen in Germany decided to use a regional climate model to see what would happen if land use in Europe changed radically. They looked what would happen with air temperature, precipitation, and temperature extremes if Europe were completely deforested to either bare land or just ground vegetation. They also considered what might happen if Europe’s cropland were converted to either evergreen or deciduous forests.
The researchers knew that climate change impacts tend to be underestimated at a regional level, “because the projected global mean temperature changes are dampened by averaging over the oceans, and are much smaller than the expected regional effects over most land areas,” the team wrote in their paper, recently published in Environmental Research Letters. “This applies to both mean and extreme effects, as changes in regional extremes can be greater than those in global mean temperature up to a factor of three.”
“We wanted to perform a quantitative analysis of how much land cover changes can affect local climate. Important transitions in the land use management sector are envisioned in near future, and we felt important to benchmark the temperature response to extreme land cover changes”said Francesco Cherubini, a professor in NTNU’s Industrial Ecology Programme, and first author of the study. “Decisions regarding land uses are frequently taken at a subnational level by regional authorities, and regional projections of temperature and precipitation effects of land cover changes can help to maximize possible synergies of climate mitigation and adaptation policies, from the local to the global scale.”
Future extreme land use changes are not as improbable as you might think. As the global population continues to grow, more land will come under pressure to produce food.
Alternatively, demand for crops for biofuels could also drive what kind of vegetation is cultivated and where.
One future vision of what the world might look like, called Shared Socio-economic Pathways, estimates that global forest areas could change from about – 500 million hectares up to + 1000 million hectares in 2100, with between 200 and 1500 million hectares of land needed to grow bioenergy crops. In fact, the higher end of this range could be realized under the most ambitious climate change mitigation targets.
Changes in land use can have a complicated effect on local and regional temperatures.
When the ground cover is altered, it changes how much water is retained by the soil or lost to evaporation. It can also affect how much sunlight the ground reflects, which scientists call albedo.
The researchers knew that other studies had shown contradictory effects, particularly from deforestation. Some showed that deforestation reduced air temperatures near the ground surface, and increased daily temperature extremes and number of hot days in the summer. Other studies found increases in the occurrence of hot dry summers.
But when the researchers ran their model to see what would happen if land was deforested, they found a slight annual cooling over the region overall, but big differences locally.
Their model showed that when forests were replaced by bare land, the temperatures cooled by just -0.06 ? regionally. The cooling was slightly greater (-0.13? regionally) if the researchers assumed that forests were replaced by herbaceous vegetation. In some locations, cooling can exceed average values of -1 C.
On their own, these regional changes may not seem like much. But when the researchers looked more closely at how these changes were distributed across the region, they found that there was a cooling in the northern and eastern part of the region, and a warming effect in western and central Europe. They also found that deforestation led to increased summer temperature extremes.
“Regional cooling from deforestation might look counter-intuitive, but it is the outcome of the interplay among many different physical processes. For example, trees tend to mask land surface and increase the amount of solar energy that is not reflected back to the space but it is kept in the biosphere to warm the climate,” said Bo Huang, a postdoc in the Industrial Ecology Programme who was one of the paper’s co-authors. “This particularly applies to areas affected by seasonal snow cover, because open land areas covered by snow are much more reflective than snow-covered forested land.”
The researchers found an annual average cooling across the whole of Europe, but with a clear latitudinal trend and seasonal variability. Despite the average cooling effects, they found that deforestation tends to increase local temperatures in summer, and increase the frequency of extreme hot events.
When the researchers ran their model to see what would happen if cropland was replaced by either evergreen or deciduous forests, they found a general warming in large areas of Europe, with a mean regional warming of 0.15 ? when the transition was to evergreen forests and 0.13 ? if the transition was to deciduous forests.
Much as in the deforestation thought experiment, the researchers found that the changes were stronger at a local scale, as much as 0.9 °C in some places. And the magnitude and significance of the warming gradually increased at high latitudes and in the eastern part of the region. Areas in western Europe actually showed a slight cooling.
Cherubini says that understanding how regional vegetation changes play out at more local levels is important as decision makers consider land management policies to mitigate or adapt to climate change.
“It is important to increase our knowledge of land-climate interactions, because many of our chances to achieve low-temperature stabilization targets are heavily dependent on how we manage our land resources,” Cherubini said. “We need more research to further validate and improve the resolution of regional climate change projections, since they are instrumental to the design and implement the best land management strategies in light of climate change mitigation or adaptation.”
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Here’s the paper: http://iopscience.iop.org/article/10.1088/1748-9326/aac794/meta
Landscape has been changing for centuries. The change from 1950 and on has been towards the greener planet. More CO2 seems to be equal with more trees and other green stuff at the earths surface and in shallow waters.
So, why do we fight this? Ideology? Most certainly ideology!
I reckon they are right, but the reasoning is ‘off target’. The real reason is that ‘climate madness’ will eventually lead to the felling of all trees to feed Drax power station in Yorkshire UK and similar mad projects including home wood burners. All in the name of saving the World from climate disaster.
“We need more research to further validate and improve the resolution of regional climate change projections, since they are instrumental to the design and implement the best land management strategies in light of climate change mitigation or adaptation.”
Frightening! They haven’t validated anything! They are creating piles of imaginary evidence to support their imaginary fears. The scary part is that they are using their musings as physical evidence that the whole world should do what they say. The argument here is that if you were good at D & D as a teenager, you should now be able to make government policy that will save the world.
https://www.google.at/search?q=medieval+findings+Grape+seeds+norwegian+wines&oq=medieval+findings+Grape+seeds+norwegian+wines&aqs=chrome.
The global predictions of climate models are bad enough. Awful. Many of their ardent supporters don’t like to mention regional predictions because they know they are even worse.
Yet these lame-brains apparently don’t even know that much. Wow. That’s a failure-and-a-half.
Have they ever accurately predicted anything on a regional level?
resources,” Cherubini said. “We need more research.”
Thereby do not cut trees down without planting more trees than were cut down.
In Sheffield they (the Labour council’s paid thugs) are about halfway through bulldozing 17,000 urban trees, turning shaded leafy city streets into barren eyesores.
They are citing ‘elf & safety’ and the supposed fact that trees cause pollution and breathing difficulties by the emission of VOCs. They have even asserted that trees cause global warming.
Emails have now been discovered, though, which show that it is merely a cynical cost-cutting exercise – rammed through behind a smokescreen of public health concern.
The culprits ought to be flogged and sent to prison.
I am the great prophet, and I have an announcement to make:
One day, you will die. The earth will cease to exist. The universe will continue to expand and cool. The sun will burn out, and the universe will eventually have no heat, no light and no life.
It will be dark, at near absolute 0 degrees, and all that will exist will be some remnants of stars and planets, but they will be in total darkness. This is what cosmologists refer to The Heat Death of the universe.
This will ALL happen, unless God exists and chooses something differently.
I figured I’d let everyone know what’s coming, in case you’re interested. Trying to control the temperature of the climate isn’t going to help with any of this.
I enjoy a certain study which I’ve pursued over the years. Recently I reread some of my papers…there were several mistakes which I need to correct as I’ve learned more, thankfully I don’t try to publish this material as there is a small number interested. It would be embarrassing to have to constantly retract then rewrite then retract. My subject has never been laid down as”pat” and can’t change with understanding. That doesn’t seem to bother these Non-Scientific scare mongers who are actually acting the place of prophets…and they are false ones at that.
Nice misrepresentation WUWT. Deforestation is not the result of warming, as you headline suggests, but the result of population pressure on land usage. If you want to rubbish the article, first report it accurately, then point out the massive global drop in birth rate, now approaching 3 kids per family, down from 7. Probably due to womens lib and womens education, that will cause a population drop in a few decades.
Then point out that Holland is the second biggest food exporter in the world, by gross tonnage, after the US, and that for such a tiny country to achieve this is a clear sign of the land usage efficiency of modern farming. And they do it cheap. They are selling chickens to Nigeria, they can produce them so cheap.
Stick to the facts WUWT, dont hype or distort. Dont be like the common alarmist media, please.
Oh, that must explain the lack of vegetation in the tropics.