Time for Time Series

In this issue of Oceanography, Holliday and Cunningham (2013) extol the significance of long-term data sets in understanding the marine environment and, in particular, climate change. The 1950s were the years of exploration, dividing the ocean up into bite-sized chunks to explore as part of the International Geophysical Year(s). The 1960s and '70s were the technological years, or at least the period when we moved from mercury thermometers and clockwork current meters to advanced electronics in the ocean. The 1980s and '90s were the big program years, tackling everything from world ocean circulation to the North Sea, though not necessarily fully resolving them. Throughout this long line of programs there have been few long time series. As Holliday and Cunningham point out, the 1990s were nearly the end of the line—quite literally—for the Ellett Line, which only survived through dogged determination and support from the World Ocean Circulation Experiment (WOCE). There are several other long-term measurement campaigns that rely heavily on individuals keeping them alive, often by fitting in with other higher-profile programs. The Atlantic Meridional Transect (AMT), the Continuous Plankton Recorder (CPR) tracks of the Sir Alistar Hardy Foundation for Ocean Science (SAHFOS), and the moorings of the Atlantic Meridional Overturning Circulation are but a few of them. The first two of these programs make use of existing research ship programs or commercial routes to gather valuable data