Study: global forest loss over past 35 years more than offset by new forest growth

Posted: August 10, 2018 by oldbrew in research, trees

The world has more natural carbon dioxide absorbers in the shape of trees than was thought, to the tune of an extra 2.2 million kilometers² relative to 1982.

A team of researchers from the University of Maryland, the State University of New York and NASA’s Goddard Space Flight Center has found that new global tree growth over the past 35 years has more than offset global tree cover losses, reports

In their paper published in the journal Nature, the group describes using satellite data to track forest growth and loss over the past 35 years and what they found by doing so.

There has been a growing consensus in recent years that because humans cut down so many trees (most particularly in the rainforests) that global tree cover is shrinking. In this new effort, the researchers have found that not to be the case. They contend that global tree cover is actually increasing.

To track global tree cover changes, the researchers studied data from advanced very high-resolution radiometers aboard a series of 16 weather satellites covering the years 1982 to 2016.

By comparing daily readings, the researchers were able to see small changes occurring regularly over a relatively long period of time—which added up to large changes. Over the entire span, the researchers found that new tree cover had offset tree cover loss by approximately 2.24 million square kilometers—which they note is approximately the size of Texas and Alaska combined.

The researchers report that most of the new tree cover occurred in places that had previously been barren, such as in deserts, tundra areas, on mountains, in cities and in other non-vegetated land.

They further report that much of the new growth came about due to efforts by humans (such as reforestation efforts in China and parts of Africa) and because of global warming—warmer temperatures have raised timberlines in some mountainous regions, and allowed forests to creep into tundra areas.

Other areas of new tree growth resulted from large farm abandonments in places like Russia and the U.S. The researchers report that their calculations showed that human activities have directly caused approximately 60 percent of new global tree growth.

They suggest their technique for monitoring tree cover could be used to predict tree cover changes in the future due to global warming.

Source here.

  1. cognog2 says:

    Thanks Oldbrew. Pleased to read this. Just hope it is true. Very predicable no mention of increased CO2 levels being a contributory factor.
    Another example of MSM CAGW Group Think.

  2. Jamie Spry says:

    Reblogged this on Climatism and commented:
    MORE forests globally will, no doubt, come as unwelcome news to the environmental movement who rely on doom and gloom to drive their misanthropic, anti-capitalist climate change agenda.

  3. JB says:

    Adding this to my personal lib. Rainforest destruction has been on my ire list for some time. I had no idea how widespread reforestation efforts have been. Thanks Oldbrew!

  4. oldbrew says:

    There has been a growing consensus in recent years that because humans cut down so many trees (most particularly in the rainforests) that global tree cover is shrinking

    Whatever this ‘consensus’ was, it has been overthrown by actual data. So perhaps not wise to rely on consensus in climate matters.

  5. willb01 says:

    If global tree cover is increasing, then global photosynthesis must also be increasing: more trees ==> more leaves ==> more photosynthesis ==> more carbon fixation. I don’t think there’s any doubt that carbon fixation through photosynthesis is by far the biggest CO2 sink in the carbon cycle. CO2 and methane used to be Earth’s predominant atmospheric gases. Now they are just trace gases thanks to photosynthesis.

    In addition to the increased tree cover, NASA satellite imagery also shows that the Earth appears to be ‘greening’ due to CO2 fertilization: more CO2 ==> increased photosynthesis efficiency + increased leaf area index ==> more carbon fixation.

    Here is a back-of-the-envelope calculation:
    Carbon fixation due to photosynthesis is currently estimated to sink 15 times the amount of carbon we humans are spewing into the atmosphere. If global photosynthesis has increased by just 10% over the past 35 years (increased tree cover + increased efficiency + increased leaf area index), then that increase should be removing 1.5 times the amount of carbon we humans are adding to the atmosphere.

  6. oldbrew says:

    If the oceans start cooling or are already doing so, that would also increase CO2 absorption.

  7. willb01 says:

    I guess my point was: If the photosynthesis sink has increased enough in 35 years so that it is now removing from the atmosphere the equivalent of all anthropogenic CO2 emissions, then where is the increase in atmospheric CO2 concentration coming from?

  8. oldbrew says:

    Will – warming oceans should be releasing CO2.

    A plausible or likely reason for rises in atmospheric CO2 following long-term global temperature increases, with a lag of a few hundred years as seen in the historic ice core records, would be ocean outgassing. Such CO2 increases are an effect, not a cause of warming.

    Volcanism could be a factor as well.

  9. oldbrew says:

    All that sunshine and plant-nourishing CO2 is a boon for crop farmers…

    Date: 11/08/18 Financial Times

    The US Department of Agriculture said the 2018 US soyabean crop would total 4.59bn bushels this autumn, up 4 per cent from last year’s record 4.39bn bushels.

    Thanks also to all the fuel-powered farm machinery of course.

  10. Adam Gallon says:

    Ah, but it’s “Rotten” corn, deficient in vitamins & minerals! 😉