The Gang Green keeps telling us that our planet is losing plant life hand over fist. Not so. Carbon Dioxide is a key part of photosynthesys - it is plant food and the more of it that goes into our atmosphere, the more plants grow.
From Human Progress:
Rejoice, the Earth Is Becoming Greener
Amid all the talk of an imminent planetary catastrophe caused by emissions of carbon dioxide, another fact is often ignored: global greening is happening faster than climate change. The amount of vegetation growing on the earth has been increasing every year for at least 30 years. The evidence comes from the growth rate of plants and from satellite data.
In 2016 a paper was published by 32 authors from 24 institutions in eight countries that analysed satellite data and concluded that there had been a roughly 14% increase in green vegetation over 30 years. The study attributed 70% of this increase to the extra carbon dioxide in the atmosphere. The lead author on the study, Zaichun Zhu of Beijing University, says this is equivalent to adding a new continent of green vegetation twice the size of the mainland United States.
Global greening has affected all ecosystems – from arctic tundra to coral reefs to plankton to tropical rain forests – but shows up most strongly in arid places like the Sahel region of Africa, where desertification has largely now reversed. This is because plants lose less water in the process of absorbing carbon dioxide if the concentration of carbon dioxide is higher. Ecosystems and farms will be less water-stressed at the end of this century than they are today during periods of low rainfall.
There should have been no surprise about this news. Thousands of experiments have been conducted over many years in which levels of CO2 had been increased over crops or wild ecosystems and boosted their growth. The owners of commercial greenhouses usually pump CO2 into the air to speed up the growth of plants. CO2 is plant food.
The original paper is at Nature:
Greening of the Earth and its drivers
Global environmental change is rapidly altering the dynamics of terrestrial vegetation, with consequences for the functioning of the Earth system and provision of ecosystem services. Yet how global vegetation is responding to the changing environment is not well established. Here we use three long-term satellite leaf area index (LAI) records and ten global ecosystem models to investigate four key drivers of LAI trends during 1982–2009. We show a persistent and widespread increase of growing season integrated LAI (greening) over 25% to 50% of the global vegetated area, whereas less than 4% of the globe shows decreasing LAI (browning). Factorial simulations with multiple global ecosystem models suggest that CO2 fertilization effects explain 70% of the observed greening trend, followed by nitrogen deposition (9%), climate change (8%) and land cover change (LCC) (4%). CO2 fertilization effects explain most of the greening trends in the tropics, whereas climate change resulted in greening of the high latitudes and the Tibetan Plateau. LCC contributed most to the regional greening observed in southeast China and the eastern United States. The regional effects of unexplained factors suggest that the next generation of ecosystem models will need to explore the impacts of forest demography, differences in regional management intensities for cropland and pastures, and other emerging productivity constraints such as phosphorus availability.
The "environmentalists" are again promoting a narrative while people like Professor Zhu are promoting facts.
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