Posted by: Saving Water SA (Cape Town, South Africa) – partnered with Water Rhapsody conservation systems – 27 May 2011
A 200-day drought in central China has provoked a fierce debate among scientists and government researchers about the impact of big dams like the Three Gorges on local weather systems.
Government officials and experts have been forced to respond to a flurry of accusations by netizens and environmental activists that the world’s biggest hydropower plant has disrupted downstream water flows and could have a long-term impact on local weather patterns.
WHY IS THE THREE GORGES BEING BLAMED?
Experts say that the 600-km (350-mile) long reservoir required to serve the 26 700-megawatt turbines at the Three Gorges hydropower plant prevents considerable volumes of water from flowing downstream.
But some environmentalists and climate specialists have also said that the reservoir acts as a giant heat reflector that affects the microclimate of the region, raising temperatures and reducing rainfall.
They also point to longer-term impact, saying that large reservoirs like the Three Gorges are net greenhouse gas producers because they submerged vast tracts of forest and farmland that would otherwise have absorbed climate-altering carbon dioxide from the atmosphere. Continue reading