Current events
I’m working my way, for the first time, through Carl Sagan’s TV series Cosmos, and last weekend I saw episode 4, “Heaven and Hell”, which compares Earth and Venus. Although the planets are similar in size, Venus is a hellish world. Runaway greenhouse warming has produced extreme heat and atmospheric pressure at the planet’s surface, which is perpetually shrouded by carbon dioxide clouds laced with sulfuric acid. Contrast this with Earth’s present conditions, which allow a marvellous diversity of living things to flourish. Sagan pointed out that we’re not guaranteed these favorable conditions forever, and in fact could be jeopardizing them by our actions. We’re tinkering with a vast complex system that we understand only poorly. Over 25 years ago, he warned of the potential dangers of the greenhouse effect here on Earth. I can’t remember if it was in the video, but in the book he also mentions the possibility of a runaway albedo effect that could leave the planet much colder (tipping us toward Martian rather than Venusian conditions). Here’s a press release for the European Space Agency’s Venus Express mission that talks about how both Mars and Venus might once have been much more Earthlike, and how we can learn from their fates information that might be vital to our own fate.
I just hope that as we continue to discover more about global warming, here or elsewhere, people will listen, learn, and act. I found this article from The Economist fairly discouraging. About the only good thing you could say about anti-science efforts to ban the teaching of evolution was that they were mostly confined to the US. That’s unpleasant for those of us who live here, but at least it seemed like a more or less contained phenomenon. But this article describes ways in which anti-evolution sentiments are extending out into the rest of the world. What can you say about a species that is smart enough to figure out where it came from but unable. in part, to accept the knowledge?
