Hopenhagen

The 15th annual UN Climate Change Conference, COP15, opened ceremoniously in Copenhagen yesterday. Over the last few days, there has been a tug of war between the hopeful and the pessimistic about whether this conference will result in consensus or policy action. I'm among the hopeful, buoyed by the push towards action by the Obama administration, which is ready to talk numbers and commitments (a 17% cut in 2005 emissions by 2020 is on the table - not very ambitious, but a start), the EPA's fresh announcement that it will regulate carbon dioxide as a pollutant, and the coverage of Copenhagen by the American press, which seems to me more intense than of past conferences - all positive indications that negotiations will make progress towards international carbon and climate regulation. My sentiments are perfectly described by the conference's concert event series, Hopenhagen, a Danish-English hybrid that rings with European cool and American optimism.

Spartina likes it hot

Some like it hot. Spartina patens, the dominant grass in New England salt marsh, does, but many salt marsh forb species, pictured above, do not. In field experiments warming areas of salt marsh on the border of Spartina grass and forb panne zones, I found that the species in the forb panne, a unique and diverse group of stress tolerant forbs, were outcompeted by Spartina under warmer conditions. Plant diversity rapidly declined in experimentally warmed plots as Spartina took over.

From these results, my co-author, Mark Bertness, and I predict declines in salt marsh plant diversity and reductions in forb panne area in the near future due to global warming. In fact, in the warm years when we did our experiment (2004-2006), forb panne area was lost even in control plots, and forb pannes were lost before our very eyes. Read all about it in this month's Ecology Letters.