SEA Currents: Robert C. Seamans
July 26, 2015
Climate Change in the Phoenix Islands
04° 29.062’ x 172° 04.473’
SE 6 knots
A major theme of both our science and policy work has centered on climate change, specifically how small islands nations like Kiribati can proceed in the face of quickly changing oceans. We’ve talked about the consequences of coral bleaching, acidification, ocean temperature increase and, most interesting to me, how the sovereignty of the small islands nations could be effected if the atolls are submerged by sea level rise.
Our data show increases in sea level temperature and changes in the thermocline, which we have attributed to this year’s strong El Nino cycle, but seeing substantial changes in only a year’s time has made me realize the strikingly dynamic nature of the ocean. After witnessing the extreme low elevation of atolls of the Phoenix group (topping out at a whooping 2-3 meters above sea level), I’ve been driven further to explore how rising sea level will affect island nations like Kiribati.
Starting early in the shore component, Will Godsey and I have been exploring literature surrounding the behavior of low laying coral atolls in the face of historic and current sea level rise. Considering that the nation of Kiribati has already purchased land in Fiji as a potential relocation site, this project became very important to us as the threat of sea level rise is imminent for these islands. Literature on the matter is mixed, some papers confirmed the common notion that when sea level rises islands submerge, but others piqued our interest in a very hopeful way. Paul Kench had discovered that some islands could accrete with sea level rise, as long as the coral flats surrounding the islands were healthy enough to supply enough sediment to balance any erosion. Other academics looked towards paleorecords from the Holocene, but time restricted us on that front.
For now, we are working with our science research mentor, Mary Engels, to determine the stratigraphic history of Kanton, Orona, and Nikumaroro, while trying to correlate this data with storm events. This will give us a sense of behaviors unique to the islands and their coral sediment supply, and we can hopefully pinpoint the erosional or accretionary rates. Kench had discovered an island in the South Pacific that gained roughly 7% each year and hopefully we can find that this is not isolated.
P.S. Happy late birthday Kailey! I hope everyone at home is doing well and thanks for helping me get here, this program has been even more than I could have imagined.