Query: The first adjustment changed how the temperature of the ocean surface is calculated, by replacing satellite data with drifting buoys and temperatures in ships’ water intake.

Relevant passages:
Sea level <=SEP=> Mean sea level ( MSL ) ( abbreviated simply sea level ) is an average level of the surface of one or more of Earth 's oceans from which heights such as elevations may be measured . MSL is a type of vertical datuma standardised geodetic reference pointthat is used , for example , as a chart datum in cartography and marine navigation , or , in aviation , as the standard sea level at which atmospheric pressure is measured in order to calibrate altitude and , consequently , aircraft flight levels . A common and relatively straightforward mean sea-level standard is the midpoint between a mean low and mean high tide at a particular location .   Sea levels can be affected by many factors and are known to have varied greatly over geological time scales . The careful measurement of variations in MSL can offer insights into ongoing climate change , and sea level rise has been widely quoted as evidence of ongoing global warming .   The term above sea level generally refers to above mean sea level ( AMSL ) .

Sea surface temperature <=SEP=> Sea surface temperature ( SST ) is the water temperature close to the ocean 's surface . The exact meaning of surface varies according to the measurement method used , but it is between 1 mm and 20 m below the sea surface . Air masses in the Earth 's atmosphere are highly modified by sea surface temperatures within a short distance of the shore . Localized areas of heavy snow can form in bands downwind of warm water bodies within an otherwise cold air mass . Warm sea surface temperatures are known to be a cause of tropical cyclogenesis over the Earth 's oceans . Tropical cyclones can also cause a cool wake , due to turbulent mixing of the upper 30 m of the ocean . SST changes diurnally , like the air above it , but to a lesser degree . There is less SST variation on breezy days than on calm days . In addition , ocean currents such as the Atlantic Multidecadal Oscillation ( AMO ) , can effect SST 's on multi-decadal time scales , a major impact results from the global thermohaline circulation , which affects average SST significantly throughout most of the world 's oceans .   Coastal SSTs can cause offshore winds to generate upwelling , which can significantly cool or warm nearby landmasses , but shallower waters over a continental shelf are often warmer . Onshore winds can cause a considerable warm-up even in areas where upwelling is fairly constant , such as the northwest coast of South America . Its values are important within numerical weather prediction as the SST influences the atmosphere above , such as in the formation of sea breezes and sea fog . It is also used to calibrate measurements from weather satellites .

Weather buoy <=SEP=> Weather buoys are instruments which collect weather and ocean data within the world 's oceans , as well as aid during emergency response to chemical spills , legal proceedings , and engineering design . Moored buoys have been in use since 1951 , while drifting buoys have been used since 1979 . Moored buoys are connected with the ocean bottom using either chains , nylon , or buoyant polypropylene . With the decline of the weather ship , they have taken a more primary role in measuring conditions over the open seas since the 1970s . During the 1980s and 1990s , a network of buoys in the central and eastern tropical Pacific Ocean helped study the El Niño-Southern Oscillation . Moored weather buoys range from 1.5 m to 12 m in diameter , while drifting buoys are smaller , with diameters of 30 cm to 40 cm . 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 .

Instrumental temperature record <=SEP=> The instrumental temperature record provides the temperature of Earth 's climate system from the historical network of in situ measurements of surface air temperatures and ocean surface temperatures . Data are collected at thousands of meteorological stations , buoys and ships around the globe . The longest-running temperature record is the Central England temperature data series , that starts in 1659 . The longest-running quasi-global record starts in 1850 . In recent decades more extensive sampling of ocean temperatures at various depths have begun allowing estimates of ocean heat content but these do not form part of the global surface temperature datasets .

Weather station <=SEP=> A weather station is a facility , either on land or sea , with instruments and equipment for measuring atmospheric conditions to provide information for weather forecasts and to study the weather and climate . The measurements taken include temperature , atmospheric pressure , humidity , wind speed , wind direction , and precipitation amounts . Wind measurements are taken with as few other obstructions as possible , while temperature and humidity measurements are kept free from direct solar radiation , or insolation . Manual observations are taken at least once daily , while automated measurements are taken at least once an hour . Weather conditions out at sea are taken by ships and buoys , which measure slightly different meteorological quantities such as sea surface temperature ( SST ) , wave height , and wave period . Drifting weather buoys outnumber their moored versions by a significant amount .