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Rise in CO2 has 'greened Planet Earth'Rise in CO2 has 'greened Planet Earth' - BBC NewsCarbon dioxide emissions from industrial society have driven a huge growth in trees and other plants.A new study says that if the extra green leaves prompted by rising CO2 levels were laid in a carpet, it would cover twice the continental USA.Climate sceptics argue the findings show that the extra CO2 is actually benefiting the planet.But the researchers say the fertilisation effect diminishes over time.
If you live in Siberia or northern Canada, a warmer Earth would result in a greener landscape.However, if you live on the edge of a desert - in China, Africa, USA or Australia, a warmer climate means more evaporation and a less-green landscape.There is another problem with plants - they work best in a particular climate. For human-bred crops, it is relatively easy for the seed distributors to deliver warm-climate strains to areas that were previously cooler climates.However, many native plants have a more limited range of seed dispersal, so they often get isolated on cooler mountains within their existing range, and get exterminated when they reach the top of the mountain. Alexander van Humboldt explored some high mountains, and we can now compare his scientific records with the distribution of species today, and we can see them climbing higher.Native forests and native staple crops can't migrate so readily, and are likely to be overrun by invasive weeds.
For an 18-month period beginning in 2010, the oceans mysteriously dropped by about 7 millimetres, more than offsetting the annual rise,” the US National Science Foundation said in a statement
A warmer earth is a wetter earth.
as they become the fertile grasslands they once were
I can see extreme weather in the short term, but this will moderate in the longer term. For example, the polar ice caps set up thermal gradients with the equators which drives ocean currents. Say the poles got warmer, these gradient will go down and slow and alter the currents. The transition will create a wild card, but then things will smooth out when the new patterns appear.
Quote from: Tim the PlumberA warmer earth is a wetter earth.Higher temperatures do mean more evaporation from oceans & lakes - but also more thunderstorms, and hurricanes/tornadoes, blizzards, floods and erosion. Climatologists expect this more energetic atmosphere to produce "more extreme" weather.
Higher temperatures also mean faster evaporation from the land, which can turn grasslands into desert.
Quoteas they become the fertile grasslands they once wereThere is evidence that where there is now desert, Australia was once covered by a forest populated by megafauna.I fear that, like many other locations on Earth, once humans arrived, any previously stable ecosystem was destroyed, resulting in deforestation and desertification. Since humans bought rabbits to Australia (in the past 200 years), it is likely to stay as a desert for a considerable time.Higher temperatures are also a concern for crop scientists, trying to work out how to produce more food for Earth's growing population. Many of the world's staple grains use C3 metabolism (because it uses a 3-carbon initial step), which becomes less efficient at higher temperatures. Some genetic engineers are thinking about how to make the wholesale genetic changes required to turn C3 crops like wheat into C4 crops like maize (using a 4-carbon initial step).Many grasses are C3.
A warmer earth is a wetter earth.
The results of this study thus bode well for the future of rice production in India during the dry season. As the CO2 concentration of the air rises, yields will increase. And if the temperature rises as models project, yields will still increase, though by not quite as much. These findings, coupled with the fact that the grain nutritional quality (as defined by an increase in amylose content) was enhanced by elevated CO2, suggest there is a bright future in store for rice in a carbon dioxide-enhanced atmosphere.