Nevertheless - increased CO2 is contributing to a greener earth.
It's mother nature's fertilizer.With CO2 Levels Rising, World’s Drylands Are Turning Green
Despite warnings that climate change would create widespread desertification, many drylands are getting greener because of increased CO2 in the air — a trend that recent studies indicate will continue. But scientists warn this added vegetation may soak up scarce water supplies.
Southeast Australia has been getting hotter and drier. Droughts have lengthened, and temperatures regularly soar above 95 degrees F (35 degrees C). Bush fires abound. But somehow, its woodlands keep growing. One of the more extreme and volatile ecosystems on the planet is defying meteorology and becoming greener.
And Australia is far from alone. From Africa’s Sahel to arid western India, and the deserts of northern China to southern Africa, the story is the same. “Greening is happening in most of the drylands globally, despite increasing aridity,” says Jason Evans, a water-cycle researcher at the Climate Change Research Centre of the University of New South Wales in Sydney, Australia.
What is going on? The primary reason, most recent studies conclude, is the 50-percent rise in carbon dioxide concentrations in the atmosphere since preindustrial times. This increased C02 is not just driving climate change, but also fast-tracking photosynthesis in plants. By allowing them to use scarce water more efficiently, the CO2-rich air fertilizes vegetation growth in even some of the driest places.
As we pump yet more CO2 into the air, arid-land greening seems set to continue, according to two recent modeling studies. But ecologists warn that, despite appearances, going green may have downsides for arid ecosystems and for the people who depend on them. Desert plants and animals will often lose out, and the extra vegetation may soak up scarce water supplies.
The negative impacts of hotter, drier climates have not gone away. But in most arid lands the CO2 fertilization effect is proving powerful.Drylands cover roughly 40 percent of the planet’s land surface. The deserts at their core are surrounded by wide expanses of savanna grass, dry woodlands, and sometimes irrigated fields. They are home to more than a third of the world’s population and are among the most biodiverse ecosystems in the world, according to the International Union for Conservation of Nature, the international organization for conservation scientists.
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https://e360.yale.edu/features/greening-drylands-carbon-dioxide-climate-change#:~:text=Despite%20warnings%20that%20climate%20change,soak%20up%20scarce%20water%20supplies.Over the past half-century, most drylands have been experiencing a decline in rainfall, along with higher temperatures and greater rates of evaporation. Many have also been degraded by poor farming practices and overgrazing of livestock. Climate scientists and ecologists alike have until recently presumed that this combination of growing meteorological aridity and pressure from human activities would lead to less vegetation. They have routinely warned of widespread desertification, which U.N. officials have called “the greatest environmental challenge of our time.”
Yet in most drylands, this anticipated desertification has not happened. Rather than shriveling and dying, vegetation is usually growing faster and expanding its terrain, while deserts are retreating. This, researchers of the world’s carbon and water cycles say, is largely due to the extra CO2 in the atmosphere.
