Yangtze drought blamed on Three Gorges Dam

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.

Climate specialists say that the reservoir acts as a giant heat reflector that affects the microclimate of the region

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