The NOAA Kuroshio Extension Observatory (KEO) buoy was first deployed in June 2004, in the recirculation gyre south of the Kuroshio Extension at 144.6°E, 32.4°N. In February 2007, JAMSTEC deployed a second KEO buoy (JKEO) north of the Kuroshio Extension at 37.9°N, 146.6°E. Both KEO moorings carry a suite of meteorological sensors to measure winds, air temperature, relative humidity, rainfall, and solar and longwave radiation. With measurements of sea surface temperature and these surface meteorological measurements, the net air-sea heat, moisture and momentum fluxes can be computed. Surface and subsurface instrumentation includes temperature and salinity at 1 m to 500 m. Daily-averaged data are available in near-realtime. In addition, both moorings carry a pCO2 sensor for computation of the air-sea CO2 flux. In the future, additional sensors may be added to the moorings.