Melting polar ice has a worrisome list of consequences—methane gas release, rising sea levels, and the liberation of long frozen 750,000-year-old microbes. While melting glaciers probably aren’t going to turn into Jurassic Park, scientists are understandably concerned how they might affect the environment. Scientific American has a new feature on the impact of these liberated microbes on ocean life:
More likely is [the] prospect that thawing ice sheets will allow ancient microbial genes to mix with modern ones, flooding the oceans with never-before-seen types of organisms. Rogers [an evolutionary biology] believes this is already taking place. “What we think is happening is that things are melting out all the time and you’re getting mixing of these old and new genotypes,” he said.
If you could watch a movie of the planet over the last several million years, you’d see the ice caps advance and retreat: The planet’s climate moves in cycles, with ice ages and interglacial periods alternating. But looking at previous interglacials similar to our own, geophysicists now think that the current mostly ice-less period may be longer than it would have been had a certain species not invented the combustion engine. Specifically, it looks like with amount of greenhouse gases we’ve already spewed into the atmosphere, the next ice age will be delayed. And before you decide that’s a good thing, at the rate we’re currently going, we’re not just pushing off the glaciers for a few geologically insignificant years: the team says that the atmospheric concentration of CO2 would to be at most 240 parts per million (ppm) before glaciation would kick in. Right now, it’s 390 ppm, with no signs of dropping and many signs of continuing to rise. When (and how) the planet’s self-regulation system will kick in isn’t clear, but the long, increasingly hot trip probably isn’t going to be pretty.
Read more at the BBC.
Image courtesy of NASA / Wikipedia