Thursday, March 20, 2008

If you have the right theory, all the facts make sense...

NPR has a story from yesterday which is pretty interesting: The Mystery of Global Warming's Missing Heat

by Richard Harris

3000 robots have been taking the Ocean's temperature the last 4-5 years and haven't seen any warming. At the same time, sea levels have risen 1/2 inch.

This is naturally very confusing: If the Earth is warming, then why isn't it actually warming? If it is not warming then why the increase in sea-level? When you warm-up water it expands, but since the water isn't warmer the expansion couldn't have been from that.

The answer is cosmic rays. Okay, I don't wear a tinfoil hat so I will explain further. When the sun is more active, as judged by sunspots, it produces a strong magnetic field. This field reduces the amount of cosmic rays which hit our atmosphere. Oh, yes. Cosmic rays seed clouds. This isn't my brilliant theory by the way.

The Chilling Stars: The New Theory of Climate Change (Paperback) by Henrik Svensmark

Clouds have multiple effects. They insulate at night, holding in warmth. But in the daytime they reflect more sunlight away than insulate--so the net effect is thought to be that clouds cool. There is one region of the earth where clouds only warm; the arctic. The reason is that places with permanent snow cover already reflect the sun very efficiently, so clouds there are only insulating. If the sun was fairly inactive (as it is and has been the last couple of years) one might expect global cooling and some melt-off of arctic ice. We haven't seen the cooling, but we also haven't seen carbon dioxide based heating either--possibly they are canceling each other out.

1 comment:

datadawak said...

Thank you for your comment on my Kyoto episode. I read your blog comment and npr HP that you referred.

Global warming is very alarming, but more I learn about it, I don't know what to believe. It is true that the rate at which the average temperature is rising fast, but in the history of the earth - in range of millions of years, it has happened before and we've had much warmer time before. I heard similar arguments from a Kyoto University and Cornell professors.

I decide to do whatever I can (without taking too much pain) not to hurt the environment. As I've posted on my blog before, I take my own chopsticks to restaurants - since I started, I've saved 41 pairs in 3 months. I try to take a hand-carry bags when I go to gorcery stores, so not requiring their plastic bags. I climb stairs instead of taking elevator and try to walk or ride a bike instead of driving. I figure, every little bit helps.