Satellite Study: slowing plant growth, 2000-2009

From NASA:

download large image (700 KB, JPEG) acquired January 1, 2000 – December 31, 2009
download large Hemispheric Trends image (81 KB, PDF)

Conventional wisdom holds that plants should thrive when temperatures warm and the growing season lengthens under a changing climate. A 2003 study showed that plant growth indeed increased as temperatures warmed between 1982 and 1999. But when researchers at the University of Montana updated the study for the last decade, 2000–2009, they discovered that even though the decade was the warmest since instrumental recordkeeping began, plant growth slowed.

The study is significant because plants soak up carbon from the atmosphere as they grow. As growth slows, the amount of carbon plants take up slows as well, leaving more carbon in the atmosphere to contribute to climate change. It is also a warning that a warming climate could bring a decrease in food and biofuel production.

Researchers Maozheng Zhou and Steven Running published the work in Science on August 20, 2010. They used data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite to monitor plant growth and calculate the total amount of carbon plants store as they grow, a value called net primary productivity. Their results are illustrated in this image, which shows the change in the amount of carbon consumed by plants between 2000 and 2009. Green areas show where plants grew more (and consumed more carbon), and brown areas show where they grew less. The deeper the color, the stronger the trend.

In general plant growth and consequently the amount of carbon plants store increased in the Northern Hemisphere and decreased in the Southern Hemisphere. The difference, say Zhou and Running, is water. Three things limit plant growth: light, water, and temperature. In the Northern Hemisphere, warmer temperatures and a longer growing season allowed plants to grow more. But in the Southern Hemisphere, drought dominated the decade. Higher temperatures dried plants and soil, generally slowing growth. The attached graphs illustrate the direct relationship between drought and the amount of carbon plants absorbed between 2000 and 2009.

During the decade, large-scale droughts, primarily in the Southern Hemisphere, were strong enough to overwhelm increased plant growth in other places, resulting in decreased plant growth overall. While 65 percent of the Northern Hemisphere’s vegetated land had increasing growth, 70 percent of the Southern Hemisphere’s vegetated land had decreasing growth. Added together, global plant growth decreased slightly in the decade, reducing carbon uptake by an estimated 0.55 petagrams, a one percent decrease.

It is too early to tell if the recent decade marks the beginning of a longer term trend in plant growth related to long-term climate change. Climate is defined by patterns seen over longer periods of time, at least 20-30 years. In the previous 20 years (1982–1999), plant growth and the related carbon uptake increased as much as six percent. Regardless, the observed decrease in plant growth between 2000 and 2009 helps researchers better understand how plants might respond to a changing climate.

“We see this as a bit of a surprise, and potentially significant on a policy level because previous interpretations suggested that global warming might actually help plant growth around the world,” Running said. “This is a pretty serious warning that warmer temperatures are not going to endlessly improve plant growth.”

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A longer NASA feature article and videos describe the results in greater detail. (below)

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From NASA

Drought Drives Decade-Long Decline in Plant Growth

A snapshot of Earth's plant productivity in 2003 shows regions of increased productivity (green) and decreased productivity (red).

> View larger

A snapshot of Earth’s plant productivity in 2003 shows regions of increased productivity (green) and decreased productivity (red). Tracking productivity between 2000 and 2009, researchers found a global net decrease due to regional drought. Credit: NASA Goddard Space Flight Center Scientific Visualization Studio


This graph shows the anomaly of carbon dioxide growth over the past decade.

> View larger

Interannual shifts in plant productivity (green line) fluctuated in step with shifts in atmospheric carbon dioxide (red line) between 2000 through 2009. Credit: Maosheng Zhao and Steven Running Earth has done an ecological about-face: Global plant productivity that once flourished under warming temperatures and a lengthened growing season is now on the decline, struck by the stress of drought.

NASA-funded researchers Maosheng Zhao and Steven Running, of the University of Montana in Missoula, discovered the global shift during an analysis of NASA satellite data. Compared with a six-percent increase spanning two earlier decades, the recent ten-year decline is slight — just one percent. The shift, however, could impact food security, biofuels, and the global carbon cycle.

“We see this as a bit of a surprise, and potentially significant on a policy level because previous interpretations suggested that global warming might actually help plant growth around the world,” Running said.

“These results are extraordinarily significant because they show that the global net effect of climatic warming on the productivity of terrestrial vegetation need not be positive — as was documented for the 1980’s and 1990’s,” said Diane Wickland, of NASA Headquarters and manager of NASA’s Terrestrial Ecology research program.

Conventional wisdom based on previous research held that land plant productivity was on the rise. A 2003 paper in Science led by then University of Montana scientist Ramakrishna Nemani (now at NASA Ames Research Center, Moffett Field, Calif.) showed that global terrestrial plant productivity increased as much as six percent between 1982 and 1999. That’s because for nearly two decades, temperature, solar radiation and water availability — influenced by climate change — were favorable for growth.

Setting out to update that analysis, Zhao and Running expected to see similar results as global average temperatures have continued to climb. Instead, they found that the impact of regional drought overwhelmed the positive influence of a longer growing season, driving down global plant productivity between 2000 and 2009. The team published their findings Aug. 20 in Science.

“This is a pretty serious warning that warmer temperatures are not going to endlessly improve plant growth,” Running said.

The discovery comes from an analysis of plant productivity data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite, combined with growing season climate variables including temperature, solar radiation and water. The plant and climate data are factored into an algorithm that describes constraints on plant growth at different geographical locations.

For example, growth is generally limited in high latitudes by temperature and in deserts by water. But regional limitations can very in their degree of impact on growth throughout the growing season.

Zhao and Running’s analysis showed that since 2000, high-latitude northern hemisphere ecosystems have continued to benefit from warmer temperatures and a longer growing season. But that effect was offset by warming-associated drought that limited growth in the southern hemisphere, resulting in a net global loss of land productivity.

“This past decade’s net decline in terrestrial productivity illustrates that a complex interplay between temperature, rainfall, cloudiness, and carbon dioxide, probably in combination with other factors such as nutrients and land management, will determine future patterns and trends in productivity,” Wickland said.

Related Links: > Related video

This narrated video gives an overview of net primary production and the carbon cycle. High-resolution data from the Moderate Resolution Imaging Spectroradiometer, or MODIS, indicate a net decrease in NPP from 2000-2009, as compared to the previous two decades. Credit: NASA/Michelle Williams

Researchers are keen on maintaining a record of the trends into the future. For one reason, plants act as a carbon dioxide “sink,” and shifting plant productivity is linked to shifting levels of the greenhouse gas in the atmosphere. Also, stresses on plant growth could challenge food production.

“The potential that future warming would cause additional declines does not bode well for the ability of the biosphere to support multiple societal demands for agricultural production, fiber needs, and increasingly, biofuel production,” Zhao said.

“Even if the declining trend of the past decade does not continue, managing forests and croplands for multiple benefits to include food production, biofuel harvest, and carbon storage may become exceedingly challenging in light of the possible impacts of such decadal-scale changes,” Wickland said.

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hunter

Does this include plant life in the oceans?

Eric Gisin

The map shows Productivity Trend from -21 to 20 g/m2. That translates to 0.21 tonnes/ha which foresters use. Annual growth rate ranges from 10 (temperate) to 50+ (trop rain) tonnes/ha. So those trends are on order 1% changes.

Gnomish

“Even if the declining trend of the past decade does not continue, managing forests and croplands for multiple benefits to include food production, biofuel harvest, and carbon storage may become exceedingly challenging in light of the possible impacts of such decadal-scale changes,” Wickland said.
By wonderful coincidence, Wickland, himself, owns no forests or croplands, so his challenge is managing other people’s – at your expense, naturally.

Carbon Sponge

Well, it HASN’T been warming during this decade, and the negative signal in Indonesia, PNG and Malasia is deforestation, not climate change.

VicV

“… the global net effect of climatic warming on the productivity of terrestrial vegetation need not be positive…”
More “proof.”
[Sigh]

papertiger

All the more reason to believe that Hansen has kept his finger firmly on the scale throughout the current decade.

OR we are NOW in global cooling!!!!!
they just look past the obvious!

stumpy

Looks like from the top pic some large tracts of earth were not included in the analysis. There is also the chance to confuse correlation with causation – did the co2 change affect plant growth, was it plants affecting co2, was it temp affecting plants and co2 etc… who really knows?

rbateman

It has NOT been warming…globally, so the conclusion that C02 does not contribute to plant growth increase is false.
Phil Jones said it has not been warming the last 10-15 yrs, possibly cooling, and the decrease is only 1%??
Sound like C02 is still the king of plant growth.
We too are Carbon life form.

Baa Humbug

The 2 images shown don’t seem to match up.
In the first one (green brown), Borneo and PNG seem to be losing biomass, whereas in the 2nd image (red green) they seem to be gaining.
Similar in other areas as well, i.e. South and North America and Africa.
Are these 2 images supposed to represent the same data?

stumpy

Do they account for deforestation and changes in land use? Do they account for the destruction of large irrigation systems that occuring in the middle east? The growth of cities? How many houses and farms cropped up in China over the last 10 years? mmmm…. what about dams, increasing extent of estuarine areas, re-creation of lost wetlands? There are to many factors here to just blame c02

“In the previous 20 years (1982–1999), plant growth and the related carbon uptake increased as much as six percent.”
“Added together, global plant growth decreased slightly in the decade, reducing carbon uptake by an estimated 0.55 petagrams, a one percent decrease.”
So, we’re back to 5% higher plant growth than prior to 1982.
Abandon ship!

1999…..The shift, however, could impact food security, biofuels, and the global carbon cycle….global terrestrial plant productivity increased as much as six percent between 1982 and 1999….driving down global plant productivity between 2000 and 2009
This looks like it is from PDO. 1976/77 to 1999 PDO was (+). Starting in 1999 PDO went (-). Don Easterbrook has talked about the PDO change and food shortages that have begun:
3:18 video

John F. Hultquist

Baa “Are these 2 images supposed to represent the same data?”
No. 2003 versus 2000 to 2009

F. Ross


“… 2000–2009, they discovered that even though the decade was the warmest since instrumental recordkeeping [sic] began, plant growth slowed. …

And if, as some posters have already alluded, the basic premise of the study– that the decade was the warmest – is false, then what?
With all the problems of even defining, much less measuring, the “global temperature”, maybe plant growth slowed because global temperatures did not rise.
GIGO

David T. Bronzich

If you look up the plant hardiness zone maps at USDA, 1960 and 1996, you may notice that the zones have shifted two bands to the south. North Texas for example used to be zone 10 in 1960, but is now zone 8.

Scarlet Pumpernickel

But does this satellite check the THICKNESS of the plant growth? You know maybe the plants are actually thicker. They do the same trick for the Ice, saying it’s too thin, so maybe the height of the plants it actually higher as CO2 makes them grow better.
So if you flew a satellite over both plants they would look the same even though it is taller

And what about the microbes in the soil? http://m.b5z.net/i/u/6128582/i/carbon_cycle_NASA_ezr.jpg they are a large part of the carbon cycle, the satellite can’t pick this up

James Sexton

Baa Humbug says:
August 22, 2010 at 9:00 pm
“The 2 images shown don’t seem to match up.”
Apparently, the second pic is from 2003. Just hoover your mouse over the pic.

Kum Dollison

This makes some sense. Our Northern Hemisphere plants, mostly, like it hot with some clouds and rain; they Don’t like it UnGodly hot, and Dry.
Doubt if it has anything to do with See Oh Two, though. More to do with “weather.” Clouds (or, in this case, the lack, thereof,) caused by highs/lows, winds, ocean currents, oscillations, etc.
The period Did start in a strong La Nina, and ended in an El Nino.

CRS, Dr.P.H.

“Three things limit plant growth: light, water, and temperature.”
Well….THAT’S a bit simplified!! Don’t forget macro (C, N, P) and micro (Mo, Fe, Ca etc.) nutrients, predation, competition, disease, genetics, etc. etc.
So far, Illinois is doing OK, but I’m jealous of Nebraska.

Richard G

They can tell all this from a satellite instrument? Looking through cloud cover? Omitting Ocean plankton? Without any 0n site biomass sampling for confirmation? Amazing! How do they do that?!.
This runs contrary to site studies that show an increased water use efficiency with increased CO2 along with increased biomass production.

James Sexton

So growth is slowing. Would that correlate with the slowing of temp increase? Reading the article, if one doesn’t carefully read it, it implies that the biosphere is retreating. Which isn’t the case. Further, it seems to imply there’s less CO2 absorption from the biosphere. But that isn’t the case if the biosphere is still growing.
Mods or Anthony or whomever controls such stuff, a suggestion if I may. It would be easier to read without the redundancy.
REPLY: Sorry, once published it stays, but I will add a page break. -Anthony

dp

I’m going to go out on a limb and suggest there’s a fourth thing plants require to grow, and that is food. Plants, given the other three, will not succeed without the fourth. Not all dirt is equal.
But wait – there’s more. Many plants require symbiosis! Forests require soil fungi, for example, and bacteria. Believe it or not, healthy growing areas require shade, too. And seeds don’t just get up and walk away – they need to be carried and buried. That requires critters.
This is why it takes so long for areas burnt to the subsoil to recover. It all has to work together.

Robert

I like that there is a 65% increase in the Northern Hemisphere, and a 70% decrease in the summer hemisphere. That goes along perfectly with Joe Bastardi’s theory that it is just a shift of the warmest temperatures northward. Warmer North, cooler South, more plant growth North, less South. seems natural and not worth any worry

I be gobsmacked.
They were very explicit that the SH plant productivity dropped due to DROUGHT not temperature. NH plant productivity increased even though temperatures increased BECAUSE THERE WERE NO DROUGHT CONDITIONS. The only logical conclusion one can draw from this is that temperature increases support plant productivity.
If they wanted to make the case that increased temperature caused the drought conditions, they may be able to make that linkage…. except that the NH didn’t have drought conditions… And I wouldn’t be surprised to learn that global precipitation as a total hasn’t varied much, just natural cycles move the droughts (and floods) around the planet on a regular basis. Much of the North American prairie had severe drought conditions in the “dirty thirties”, long before CO2 had risen significantly, and those conditions have not returned since it has risen significantly. Should I conclude that increased CO2 prevents droughts? The evidence for that is about as strong as the evidence that it caused drought in the SH.

It seems the nitrogen fixation by plants is reduced at high levels of CO2 also; in particular C3 plants. The experiment which refers to this problem with the nitrogen fixation at high concentrations of CO2 was published at http://www.pnas.org/content/101/31/11506.full.pdf
On the other hand, we know that C3 plants growth starts slowing at temperatures above 20-25 °C (Odum, Eugene P. and Barrel, Gary W. Fundamentos de Ecología-Quinta Edición. 2006. International Thompson Editores, S. A. de C. V. México, Distrito Federal. Pp. 48-50). The advantage of C3 plants over C4 plants is that C3 plants survive to cold temperatures. 20 °C is the peak temperature at which the growth of C3 plants is optimum. Below and above this temperature the growth of C3 plants unavoidably slows; even if the CO2 in the environment is abundant.
I have insisted frequently on these failures on plant physiology under diverse shifts on the ecological conditions. The status on this situation is that, on biological problems, we cannot oversimplify from particular experiments, to be precise, in biology we must always have in mind the axiom that says: “The whole is much greater that the sum of its parts”.

Leon Brozyna

Increase the CO2 levels all you want; it still won’t do you any good in the face of a major drought. And just look at that — a hemispheric decadal drought coupled with increasing levels of Antarctic sea ice. Fascinating. Meanwhile, the rest of the planet keeps on greening.

John F. Hultquist

Let’s say Earth’s atmosphere warmed during a time that by happenstance
wetness was widespread and CO2 was increasing. Green plants naturally expand their area and also grow better and are planted where they had been absent for years. Following this the general wetness stalls and shifts to more concentrated areas or to over the oceans. Temperature and CO2 are not changing much but the areal expansion and productivity also stall and begin to regress. Thus, there is a slight overall decrease.
However, it is beyond me how both the prior “good” period of wetness and expansion and the more recent “bad” period of little or no temperature increase along with drought can have the same cause. One will have to produce an argument with multiple twists and turns to fit the facts into a coherent explanation.
Here is another twist. Regarding the time period 1953 to 1993, there is a report on part of the Sahel, here:
http://www.eden-foundation.org/project/desertif.html
“ Nowadays Malam Garba’s field is three times larger, but his harvest is only 1/7 of what it used to be 40 years ago. … This is just sufficient for his family. The lower yields have been caused by the destruction of perennials that used to shelter the annuals and contribute to soil fertility.”
The big news then wasn’t global warming, it was “desertification” and the magazines and newspapers and TV were consumed by it. Following this – as explained in this post, and elsewhere, there was a “greening” that now seems to have stopped.
These broad cyclical patterns should not be happening with just slow CO2 growth and global warming. It seems some one a single simple answer and there isn’t one.

P.G. Sharrow

Plants can’t tell lies. People will tell you any story they want you to hear. pg

MikeC

Look at all the pleading twards public policy in this one… boy these guys are getting desparate… I say cut NASA’s budget to help kick start paying down the deficit

kwik

“…..leaving more carbon in the atmosphere to contribute to climate change.”
Aha. Warmers at work.

Another example of cherry-picking and statistical santerism.
Southern Africa: not much of a trend
http://climexp.knmi.nl/data/iprca_15-40E_-15–35N_na.png
Argentina:
http://climexp.knmi.nl/data/iprca_290-305E_-20–40N_na.png
By selecting 2009 as end year, those “researchers” get decadal precipitation trend falling down, however, when updating to 2010, there is not much of it.. and more, precipitation is now reaching the levels in the early part of 20th century.

There was no warming in 2000-2009.
Why plant growth would not slow down?
This is called “science”?

John Silver

Is the variation within one standard deviation?

Did I miss something?
So plant growth increased by 6% and has now decreased by 1%. So I should be 1% less afraid of the TRIFFID which is tapping on my window trying to get inside to sit by the fire!!

Volt Aire

Looks like the areas doing extremely “bad” are the ones that have their rainforests cut down to produce biofuel and other land use issues regarding removal of forests to support the polpulace.
I am no expert but I will make 2 claims:
1 acre of rainforest grows more biomass than 1 acre of dead, cut down, rainforest.
and
Annual changes in plant growth are many orders of magnitude greater for natural reasons than “measured” in the article and claimed for co2.

björn

Another proxy showing a cooling trend.
This is Lysenkoism, the theory is always right, it is nature who is behaving wrong.
Solution: Destroy real data and replace with politically corrected data.

simpleseekeraftertruth

I think that all that was shown by this study was a confirmation of general understanding that water is significant to plant growth, viz:
Northern hemisphere, no drought, increased growth.
Southern hemisphere, drought, reduced growth.
All other considerations being equal.

quote
“These results are extraordinarily significant because they show that the global net effect of climatic warming on the productivity of terrestrial vegetation need not be positive — as was documented for the 1980’s and 1990’s,” said Diane Wickland, of NASA Headquarters and manager of NASA’s Terrestrial Ecology research program.
unquote
Professor Running,
If your analysis is correct (I have no reason to suppose it is not although you will get people who question it — some people will question anything), you have failed to carry your conclusion on to the next question. In a warming world there should be more water vapour (required for the positive water vapour greenhouse feedback that the models use) which one might naively assume means more precipitation, not less. So you have demonstrated that a warming world is dryer.
Any suggestions why? I realise that this is peripheral to biology but climate science is a very flexible discipline — a geology and geophysics doctorate allows one to become the leading expert after all — and the role of the ocean surface (the boundary layer so-called) in the production of biological CCNs puts it firmly in your area of expertise. Cuff a passing post-doc and set him to checking the records of oceanic biological CCNs measured over the last…. well as far back as you can go. Tell him to look at all the CCNs while he’s at it.
Invite me to the Nobel ceremony please.
JF
(Please excuse me from banging on about the Kriegesmarine Hypothesis one more time. The increased surface salinity in the oceans, BTW, seems to show that the reduction in CCNs — leading to precipitation reduction and thus less dilution of the surface waters — is more important than the increased coalescence and thus raining out of clouds. The clouds, in other words, don’t form, rather than form and then rain and thin more rapidly.
If I were an Australian I’d be checking ocean currents to see where the oceanic surface oil and surfactant pollution from India and southern China is going: it won’t all be warming the Andaman Sea and, as those two giants industrialise, the run-off is going to dry the west coast. Hint: look at Australian pan evaporation rates.)

Alan the Brit

As others have pointed out global temps have not increased over that timeframe. Did they consider the obvious as well, like seasonal variation from hemisphere to hemisphere, land management, agricultural practices generally, crop varieties, general plant variation across hemispheres?
“The plant and climate data are factored into an algorithm that describes constraints on plant growth at different geographical locations.” Are, that all important AlGorerithm, thought this was some kind of contraception technique!

son of mulder

Ah, ah another divergence

John Marshall

When temperatures rise so less CO2 is adsorbed by the oceans leaving more for plants to feed on. Plants respond to CO2 more than temperature.
Plant growth is governed by many chaotic inputs so why concentrate on but one. This does not seem to be science to me but a system to prove a point and give government more leverage to increase taxes and control our lives.

Lawrie Ayres

There didn’t seem to be any on ground confirmation of productivity. Nor were a myriad of crop and growth factors taken into account. In China for example there are less farmers and they are older. Makes a difference. Also there has been a significant increase in population which would lead to forrests being replaced by crops. After all 60 million extra people is an increase of 1 percent. There was a large rise in the cost of nitrogenous fertilizers during this time. Probably the biggest factor is the slowing of the nearly annual productivity improvement in many crops. The green revolution of the 70s has all but petered out.
All in all there are any number of reasons for a 1% decrease in growth none of which include CO2 or temperature.

papertiger

It’s really my fault.
I stopped watering the backyard this year.
Sorry.
I’ll turn the sprinklers back on tomorrow. Next week we’ll be right as rain.

There have always been variations in crops of any kind which are grown out of doors, in soils and in whatever arrives as weather and a 1% fall in growth must fall within accepted natural variability. And we define those who divine the future from studying chicken entrails as primitives?

Tenuc

Another ill thought through paper which simplifies the factors upon which plant growth depends to show a tiny change which is beyond our technology to measure accurately.
Yet another example of cargo cult science which produces the answers the researchers expect to see.

david

Re. davidmhoffer says:
August 22, 2010 at 9:54 pm
I be gobsmacked.
They were very explicit that the SH plant productivity dropped due to DROUGHT not temperature. NH plant productivity increased even though temperatures increased BECAUSE THERE WERE NO DROUGHT CONDITIONS. The only logical conclusion one can draw from this is that temperature increases support plant productivity.
I thought this ias well. I remember that the
We see this as a bit of a surprise, and potentially significant on a policy level because previous interpretations suggested that global warming might actually help plant growth around the world,” Running said.
“These results are extraordinarily significant because they show that the global net effect of climatic warming on the productivity of terrestrial vegetation need not be positive — as was documented for the 1980’s and 1990’s,” said Diane Wickland, of NASA Headquarters and manager of NASA’s Terrestrial Ecology research program.
Amazing general statements that are very serious. I thought scientist had to back up their claims, offer other possible explanations, (There are dozens not even mentioned) show the satelite measured warming rates in specific areas, demonstrate that the drought areas were not natural, ( I thought anything less then 30 years is just weather?) show charts and graphs with error bars, given such extrordinary claims. I guess general alarmist statements are the normal now. If we in fact had unusual drought, then without the increase in CO-2 the 1% decline in plant growth would have been greater.

Don Keiller

Interestingly A recent paper by Jones (Jones, P.D., D.E. Parker, T.J. Osborn, and K.R. Briffa. 2010. Global and hemispheric temperature anomalies—land and marine instrumental records. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A. doi: 10.3334/CDIAC/cli.002) shows that the Southern Hemisphere is warming significantly more slowly than the Northern.
Yet Zhou and Running’s paper shows reduced (1% over a decade!!) NPP in the South, yet an increase in the WARMER North.
Pretty poor evidence that Global WARMING has an adverse effect.
When you read deeper it is all down to increased drought over the last decade in the Southern Hemisphere.
Of course this is “unprecedented” and all sorts of Doom may follow unless you give us more money to investigate further.

steveta_uk

Surely the fact that you can clearly see the border between Malaysia and Thailand on the top image shows this is a political map, not a climatology map.
As previously noted, nothing but deforestation could have caused this.

david

Sorry, very late and poorly written.
Extrordinary broad alarmist claims from these “scientist”
No other reasons offered, even though their could be dozens.
No detailed explanation of vague alarmist warnings based on a minor 1% decline.
No error bars associated with alarmist warnings.
Is this science?