Planting forests of quick-growing trees in the world’s most arid deserts and sustaining them with desalinated water from nearby oceans would cool the regions significantly and draw down billions of tons of carbon dioxide, according to climate simulations being published in the journal Climatic Change. The concept, proposed by cell biologist Leonard Ornstein of the Mount Sinai School of Medicine in New York, includes transporting desalinated water to parched deserts with aqueducts and pumps to support growth of such heat-resistant trees as eucalyptus. By watering the plants with drip irrigation, in which water is sent directly to the trees’ roots via plastic tubing, engineers could reduce water loss, says Ornstein, who calculated the climatic effects with NASA modelers. According to the models, planting heat-resistant trees in the Sahara Desert or the Australian outback could draw down about 8 billion tons of carbon annually. In the case of the Sahara, temperatures in the forests could drop by as much as 8°C. The costs of building and running reverse-osmosis plants for desalination and transporting the water would be about $2 trillion per year. “Any solution to climate change has to be a multitrillion-dollar project,” Ornstein says. “The issue is what the payback is.”
Why does this solution sound like a forest of plastic to me? Is drip irrigating a forest with desalinated water a serious carbon sink or is it a project with a hefty carbon source? Will this forest ever get to a self-sustaining state without finding some way to manipulate the air and water currents - not to mention human behaviors - that create the deserts in the first place? And won't they suck out any remaining natural groundwater once they've been started?
An army of maintenance engineers would be needed to repair the forest.
Should any of the equipment in the irrigation pipeline fail, the affected stand of eucalyptus will turn into "fuel."
Desertification is a challenge to reverse. This is a nice jobs program, though.
We must defeat the deserts in the wetlands. The enemy still has the initiative. Armies of Typha, water hyacinth, and other aquatic weeds choke the waters of the world, drastically increasing water loss to evapotranspiration, and clogging streams and lakes with silt. Restoring our wetlands will enable them to naturally restore our drylands. The enormous efforts required for this can be financed through biofuels. Typha is a particularly good feedstock for many forms of biofuel. The accumulated silt that must be cleared can be used to rehabilitate soils and fight erosion. Environmental side effects of clearing the wetlands can be expected to include reductions in: flooding; malaria; and pests like Quelea. We are not helpless against climate change, but the work to be done is enormous.
Why not ask Monsanto et. al. to stop destroying the rainforests and greening up the deserts instead for the use of agro-fuel and GM crops if it really was that easy.
Is it possible to contact Dr. L. Ornstein ? We have similar ideas and would like to start a "conversation" with Dr. Ornstein.
Tel +852 2813 2431