Three new studies of how the world works show that seabird excrement plays an unexpected role, as do polar algae and rotting trees.
The world’s seabirds don’t just live off the land, they also nourish it: their excrement delivers 591,000 tons of nitrogen and 99,000 tons of phosphorus to feed plant communities in the soil and the water.
One polar plant community that happens to be flourishing is now to be found on the surface of Greenland’s icecap: green things are growing so well they are darkening the surface, which then reflects less light and absorbs more warmth. This algal darkening could be responsible for at least 5%, and possibly 10%, of the island’s total ice melt each summer.
And although the Arctic tundra wetlands are known to deliver between 16 and 27 million tons of methane to the atmosphere every year, they have unexpected competition in the natural greenhouse gas emission stakes.