Weather buoy tropical Pacific Ocean helped study the El Niño-Southern Oscillation. Moored weather buoys range from in diameter, while drifting buoys are smaller, with diameters of . Drifting buoys are the dominant form of weather buoy in sheer number, with 1250 located worldwide. Wind data from buoys has smaller error than that from ships. There are differences in the values of sea surface temperature measurements between the two platforms as well, relating to the depth of the measurement and whether or not the water is heated by the ship which measures the quantity. The first known proposal for surface weather observations at
Sea surface temperature satellite-derived SSTs within cloudy areas. However, passive microwave techniques can accurately measure SST and penetrate cloud cover. Within atmospheric sounder channels on weather satellites, which peak just above the ocean's surface, knowledge of the sea surface temperature is important to their calibration. The SST has a diurnal range, just like the Earth's atmosphere above, though to a lesser degree due to its greater specific heat. On calm days, the temperature can vary by . The temperature of the ocean at depth lags the Earth's atmosphere temperature by 15 days per , which means for locations like the Aral Sea, temperatures