quarta-feira, 25 de maio de 2011

Micronesia sea level

A year and a half ago, Tuvalu was complaining. Now, it's Micronesia. They are starting a lawsuit against a Czech coal power plant, in Prunéřov. Greenpeace has gotten involved, and in there own words:

The landmark legal paper, written by FSM, Greenpeace and the Environmental Law Service, and presented today at the Threatened Island Nations Climate Conference in New York’s Columbia University, offers hope to vulnerable countries on the frontline of climate impacts. FSM is one of many nation states experiencing environmental disasters, such as flooding, tidal surges and destruction of food crops, which are already exacerbated by climate change.

So, lets see what is happening to Micronesia's sea level. As usual, we start in nearby Hawaii, in their GLOSS database, at the University of Hawaii Sea Level Center. The fastest way is to check the monthly graphs for Pohnpei, Yap and Kapingamarangi, displayed below:

Looks like sea level is going up in Pohnpei and Kapingamarangi, but not in Yap. Why might that be? Checking the data and graph in detail, one sees that Yap has all the recent data, but Pohnpei and Kapingamarangi lack data, especially Kapingamarangi, which doesn't show the decline in 2010. Careful analysis of the graphs show that the highest levels in recent years have similar values in the 80s and 90s...

But more data is being concealed. If one grabs the daily data for Yap, and plots all those daily measurements into a graph, you'll get the one below:

There is data since 1969! While there seems to be a growing trend since the beginning of the nineties, the truth is that the highest values since mid-2002 are lower than the higher values in the mid seventies, and lower than several peaks in 1984, 1998, 1999, 2000, 2001 and 2002. The lowest value in 2010 is lower than any value from 1969 till 1980!