Thursday, January 16, 2014
Our planet to remain habitable for longer than previously thought - Houston Chronicle
As our star brightens and heats up during the coming millennia eventually Earth will become uninhabitable. According to one calculation, in about 2.8 billion years the last life on Earth, single-celled, heat-loving organisms in isolated pools of hot, salty water will die.
For humans, of course, the end of Earth as a habitable planet will come far sooner.
But there’s good news, friends!
Setting aside valid concerns of global warming, and computing the input only from the Sun, previous estimates have pegged the habitable period of Earth at about 650 million years. After that it’s just too hot.
But now a new, much higher resolution model suggests Earth will remain habitable to humans for much longer, perhaps as much as 1.5 billion years.
According to the study, published in Geophysical Research Letters (see abstract), increasing solar luminosity will increase the Earth’s average temperature to about 104 degrees Fahrenheit over the next 1.5 billion years.
The study authors say that’s nearly double the current global surface temperature of 58 degrees Fahrenheit, but areas near and just below the Arctic Circle would be habitable, akin to the tropics today. And there would be a LOT of rain as the oceans evaporated.
If humanity is to survive the next 1.5 billion years, an achievement I consider highly unlikely, the good news is that we’re beginning to find a lot of planets around a lot of other worlds.
In the last 100 years we’ve gone from a 12-second flight by the Wright brothers to living in space. Given that there are a lot of other worlds, humans will eventually have the capacity to reach them in plenty of time.Read here.http://blog.chron.com/sciguy/2014/01/good-news-our-planet-to-remain-habitable-for-longer-than-previously-thought/?cmpid=staffblogshcat