Stories tagged drought

Amazon Rainforest: Rainforest could become desert. photo from NASA

Amazon rainforest could become a desert

And that could speed up global warming with 'incalculable consequences', says alarming new research. Studies by the blue-chip Woods Hole Research Centre, carried out in Amazonia, have concluded that the forest cannot withstand more than two consecutive years of drought without breaking down. And that process, which would be irreversible, could begin as early as next year.

The Amazon rainforest is huge

For those who'd like some perspective, the Amazon rainforest represents half the rainforests in the world. It encompasses 1.2 billion acres, or 1.875 million square miles. That's 3.25% of the planets land mass. That’s a huge chunk of land. So if this report is accurate, it’s far from being insignificant.
The Amazon now appears to be entering its second successive year of drought, raising the possibility that it could start dying next year. The immense forest contains 90 billion tons of carbon, enough in itself to increase the rate of global warming by 50 per cent.
Read more from The Independent (U.K.), July 23, 2006

Tags : global warming, drought, amazon, rainforest, tipping point, you hdf

read more... | add a comment | share

Seagull Lake Island Fire: Photo Courtesy of Carol DeSain

Two months ago I spent a week canoeing, portaging, and camping in the Boundary Waters Canoe Area. I visited many lakes, including Seagull Lake at the end of the Gunflint Trail. Today, the landscape of some of the lakes I visited is changing dramatically as fires move through the area. The Cavity Lake Fire is presently spanning about 22,000 acres. It is hard for me to imagine that some of the serene forests I awed at and some of the campsites I relaxed at are now merely ashes.

The wildfires in northern Minnesota got me thinking about the science behind forest fires. Forest fires (also called wildfires) are a natural occurrence. Lightning is the most common natural cause of the fires. Human carelessness and arson are unnatural causes. Droughts in the summer and high winds in the fall make areas more susceptible to forest fires.

The Cavity Lake Fire is a result of lightning. The drought conditions have created a dry wooded environment. Anyone who has a fireplace knows that the driest wood burns the best.

Also, this fire is moving through an area full of debris left over from a blowdown from a storm in 1999. There is unfortunately plenty of fuel to keep this fire going.

Most of the damage from this fire may not be apparent until it's over. The after effects of forest fires can be even more harmful than the fires themselves. Erosion, introduction of invasive species, landslides, and changes in water quality are a few of these negative outcomes.

While wildfires sound like a horrible catastrophe, they can actually be beneficial for an ecosystem. Periodic fires can help the overall health of the forest. They are important for nutrient cycling, improving habitats, and maintaining biodiversity.

It can actually be more harmful to prevent wildfires than to let them happen naturally. Suppression can lead to more dangerous and hotter fires, because the time without fires allows more time for debris to accumulate.

I am interested in revisiting Seagull Lake to see how the fire has altered the ecosystem I remember. From the photos, I can see it beginning to change.

Tags : drought, forest fires, wildfires, Boundary Waters Canoe Area, lightning

read more... | add a comment | share