% This file contains a brief summary of the changes in Earth's global average % surface temperature estimated by combining the Berkeley Earth land-surface % temperature field with a reinterpolated version of the HadSST ocean temperature % field. % % Two versions of this average are reported. These differ in how they treat % locations with sea ice. In the first version, temperature anomalies in the % presence of sea ice are extrapolated from land-surface air temperature anomalies. % In the second version, temperature anomalies in the presence of sea ice are % extrapolated from sea-surface water temperature anomalies (usually collected % from open water areas on the periphery of the sea ice). For most of the % ocean, sea-surface temperatures are similar to near-surface air temperatures; % however, air temperatures above sea ice can differ substantially from the water % below the sea ice. The air temperature version of this average shows larger % changes in the recent period, in part this is because water temperature changes % are limited by the freezing point of ocean water. We believe that the use of air % temperatures above sea ice provides a more natural means of describing changes in % Earth's surface temperature. % % The percent coverage of sea ice was taken from the HadISST dataset and varies % by month and location. In the typical month, between 3.5% and 5.5% of the % Earth's surface is covered with sea ice. Prior to 1900, the ice field merely % repeats a seasonal climatology and is not directly constrained by observations. % For more information on the processing and use of HadISST and HadSST refer to % the description file for the combined gridded data product. % % Temperatures are in Celsius and reported as anomalies % relative to the Jan 1951-Dec 1980 average. Uncertainties represent the 95% confidence % interval for statistical and spatial undersampling effects as well as ocean biases. % % % The land analysis was run on 12-Mar-2019 08:22:40 % The ocean analysis was published on 20-Mar-2019 00:59:12 % % The land component is based on 45756 time series % with 18875309 monthly data points % % The ocean component is based on 376898952 instantaneous % water temperature observations % % Estimated Jan 1951-Dec 1980 global mean temperature (C) % Using air temperature above sea ice: 14.184 +/- 0.046 % Using water temperature below sea ice: 14.729 +/- 0.046 % % % Land + Ocean anomaly using air temperature above sea ice Land + Ocean using water temperature below sea ice % Year, Annual Anomaly, Annual Unc., Five-year Anomaly, Five-year Unc., Annual Anomaly, Annual Unc., Five-year Anomaly, Five-year Unc. 1850 -0.526 0.159 NaN NaN -0.477 0.146 NaN NaN 1851 -0.400 0.179 NaN NaN -0.369 0.161 NaN NaN 1852 -0.388 0.179 -0.418 0.110 -0.347 0.161 -0.380 0.101 1853 -0.413 0.134 -0.380 0.102 -0.377 0.125 -0.342 0.094 1854 -0.361 0.128 -0.396 0.087 -0.329 0.119 -0.356 0.082 1855 -0.336 0.124 -0.442 0.081 -0.288 0.117 -0.399 0.077 1856 -0.480 0.117 -0.453 0.082 -0.440 0.110 -0.409 0.078 1857 -0.620 0.134 -0.462 0.088 -0.559 0.125 -0.418 0.083 1858 -0.468 0.135 -0.488 0.093 -0.427 0.125 -0.447 0.087 1859 -0.405 0.146 -0.507 0.103 -0.374 0.134 -0.464 0.097 1860 -0.469 0.139 -0.514 0.114 -0.435 0.130 -0.468 0.106 1861 -0.573 0.160 -0.505 0.128 -0.523 0.150 -0.458 0.120 1862 -0.655 0.207 -0.512 0.139 -0.583 0.188 -0.464 0.131 1863 -0.421 0.173 -0.487 0.148 -0.375 0.168 -0.439 0.141 1864 -0.443 0.160 -0.429 0.143 -0.404 0.150 -0.383 0.139 1865 -0.340 0.174 -0.350 0.134 -0.307 0.171 -0.316 0.135 1866 -0.283 0.156 -0.316 0.121 -0.247 0.154 -0.283 0.123 1867 -0.262 0.145 -0.281 0.110 -0.245 0.146 -0.252 0.114 1868 -0.250 0.132 -0.282 0.096 -0.211 0.132 -0.255 0.099 1869 -0.270 0.137 -0.300 0.089 -0.252 0.128 -0.271 0.089 1870 -0.342 0.124 -0.316 0.081 -0.319 0.117 -0.284 0.080 1871 -0.373 0.112 -0.328 0.076 -0.328 0.108 -0.297 0.074 1872 -0.346 0.105 -0.350 0.073 -0.312 0.102 -0.321 0.072 1873 -0.310 0.104 -0.367 0.070 -0.276 0.102 -0.333 0.069 1874 -0.381 0.104 -0.377 0.068 -0.369 0.102 -0.345 0.068 1875 -0.425 0.106 -0.316 0.070 -0.380 0.103 -0.286 0.070 1876 -0.424 0.091 -0.243 0.069 -0.387 0.093 -0.220 0.068 1877 -0.040 0.107 -0.223 0.067 -0.021 0.105 -0.196 0.067 1878 0.056 0.096 -0.207 0.072 0.056 0.095 -0.181 0.070 1879 -0.284 0.096 -0.171 0.074 -0.247 0.093 -0.147 0.071 1880 -0.344 0.120 -0.223 0.072 -0.304 0.112 -0.193 0.069 1881 -0.244 0.090 -0.305 0.075 -0.217 0.089 -0.269 0.071 1882 -0.300 0.093 -0.351 0.076 -0.251 0.091 -0.310 0.071 1883 -0.353 0.095 -0.380 0.078 -0.324 0.091 -0.336 0.072 1884 -0.514 0.092 -0.435 0.084 -0.452 0.088 -0.386 0.076 1885 -0.490 0.128 -0.483 0.085 -0.437 0.115 -0.431 0.076 1886 -0.518 0.113 -0.482 0.087 -0.467 0.103 -0.428 0.078 1887 -0.542 0.091 -0.423 0.081 -0.476 0.087 -0.375 0.073 1888 -0.346 0.102 -0.425 0.070 -0.305 0.095 -0.379 0.065 1889 -0.220 0.083 -0.402 0.064 -0.191 0.083 -0.356 0.062 1890 -0.501 0.085 -0.381 0.064 -0.455 0.086 -0.342 0.063 1891 -0.400 0.089 -0.396 0.061 -0.353 0.091 -0.359 0.061 1892 -0.437 0.094 -0.435 0.063 -0.403 0.093 -0.395 0.063 1893 -0.424 0.090 -0.406 0.066 -0.390 0.090 -0.368 0.065 1894 -0.414 0.085 -0.377 0.069 -0.373 0.086 -0.339 0.067 1895 -0.354 0.095 -0.338 0.069 -0.319 0.095 -0.303 0.067 1896 -0.257 0.099 -0.341 0.068 -0.211 0.097 -0.306 0.066 1897 -0.241 0.094 -0.313 0.066 -0.222 0.093 -0.280 0.064 1898 -0.439 0.085 -0.274 0.065 -0.404 0.085 -0.246 0.063 1899 -0.273 0.082 -0.269 0.064 -0.245 0.083 -0.248 0.062 1900 -0.161 0.088 -0.296 0.063 -0.149 0.088 -0.271 0.061 1901 -0.233 0.091 -0.303 0.061 -0.220 0.090 -0.281 0.060 1902 -0.372 0.083 -0.352 0.060 -0.337 0.084 -0.330 0.058 1903 -0.474 0.077 -0.391 0.058 -0.452 0.079 -0.367 0.057 1904 -0.518 0.077 -0.401 0.055 -0.490 0.079 -0.374 0.055 1905 -0.357 0.081 -0.418 0.054 -0.334 0.082 -0.390 0.054 1906 -0.283 0.081 -0.418 0.053 -0.259 0.082 -0.390 0.053 1907 -0.456 0.078 -0.421 0.053 -0.414 0.080 -0.392 0.052 1908 -0.474 0.075 -0.451 0.052 -0.455 0.077 -0.420 0.052 1909 -0.535 0.071 -0.499 0.051 -0.496 0.073 -0.471 0.051 1910 -0.507 0.075 -0.499 0.050 -0.473 0.076 -0.472 0.050 1911 -0.524 0.075 -0.487 0.049 -0.517 0.076 -0.457 0.049 1912 -0.455 0.074 -0.428 0.050 -0.419 0.075 -0.401 0.050 1913 -0.413 0.069 -0.362 0.050 -0.381 0.070 -0.336 0.050 1914 -0.241 0.077 -0.341 0.049 -0.214 0.078 -0.310 0.050 1915 -0.178 0.079 -0.357 0.051 -0.151 0.083 -0.323 0.053 1916 -0.419 0.081 -0.349 0.053 -0.386 0.085 -0.314 0.055 1917 -0.532 0.080 -0.359 0.055 -0.485 0.084 -0.328 0.057 1918 -0.374 0.080 -0.379 0.055 -0.334 0.083 -0.352 0.058 1919 -0.293 0.081 -0.337 0.054 -0.285 0.085 -0.314 0.056 1920 -0.279 0.079 -0.292 0.051 -0.269 0.082 -0.275 0.053 1921 -0.209 0.073 -0.273 0.050 -0.197 0.076 -0.263 0.052 1922 -0.303 0.070 -0.270 0.048 -0.288 0.072 -0.259 0.050 1923 -0.283 0.069 -0.260 0.047 -0.274 0.071 -0.248 0.049 1924 -0.275 0.069 -0.236 0.047 -0.265 0.071 -0.222 0.048 1925 -0.232 0.069 -0.216 0.047 -0.217 0.072 -0.202 0.048 1926 -0.087 0.067 -0.196 0.047 -0.067 0.069 -0.182 0.048 1927 -0.204 0.064 -0.216 0.046 -0.189 0.066 -0.197 0.048 1928 -0.183 0.065 -0.200 0.046 -0.174 0.067 -0.183 0.047 1929 -0.375 0.065 -0.201 0.046 -0.340 0.067 -0.187 0.047 1930 -0.152 0.066 -0.186 0.045 -0.146 0.068 -0.175 0.046 1931 -0.092 0.066 -0.213 0.044 -0.088 0.068 -0.199 0.046 1932 -0.127 0.060 -0.173 0.043 -0.125 0.062 -0.165 0.045 1933 -0.318 0.065 -0.187 0.043 -0.297 0.066 -0.175 0.044 1934 -0.178 0.063 -0.202 0.042 -0.168 0.065 -0.187 0.043 1935 -0.220 0.063 -0.176 0.043 -0.197 0.065 -0.165 0.044 1936 -0.167 0.063 -0.111 0.043 -0.149 0.064 -0.108 0.043 1937 0.002 0.065 -0.080 0.044 -0.012 0.066 -0.075 0.044 1938 0.008 0.066 -0.021 0.045 -0.016 0.068 -0.025 0.045 1939 -0.023 0.073 0.023 0.046 -0.004 0.075 0.020 0.047 1940 0.074 0.073 0.024 0.049 0.058 0.076 0.027 0.051 1941 0.053 0.075 0.033 0.054 0.075 0.079 0.038 0.057 1942 0.010 0.084 0.067 0.059 0.022 0.089 0.067 0.062 1943 0.052 0.086 0.053 0.063 0.039 0.091 0.059 0.066 1944 0.144 0.086 0.031 0.060 0.140 0.090 0.036 0.063 1945 0.007 0.085 0.037 0.055 0.021 0.089 0.033 0.058 1946 -0.061 0.083 0.011 0.054 -0.043 0.088 0.015 0.057 1947 0.040 0.085 -0.038 0.055 0.007 0.090 -0.030 0.059 1948 -0.074 0.088 -0.074 0.059 -0.050 0.094 -0.067 0.063 1949 -0.103 0.071 -0.062 0.056 -0.085 0.075 -0.058 0.060 1950 -0.173 0.068 -0.056 0.053 -0.166 0.071 -0.047 0.056 1951 -0.000 0.064 -0.015 0.050 0.006 0.068 -0.014 0.052 1952 0.070 0.067 -0.007 0.048 0.058 0.070 -0.011 0.051 1953 0.131 0.068 0.005 0.047 0.115 0.070 -0.003 0.049 1954 -0.062 0.066 -0.030 0.045 -0.069 0.070 -0.042 0.047 1955 -0.111 0.063 -0.031 0.043 -0.122 0.066 -0.040 0.045 1956 -0.178 0.056 -0.044 0.041 -0.193 0.059 -0.047 0.043 1957 0.065 0.067 -0.024 0.040 0.070 0.067 -0.025 0.042 1958 0.064 0.055 -0.004 0.037 0.081 0.058 -0.001 0.039 1959 0.038 0.052 0.046 0.036 0.041 0.056 0.054 0.038 1960 -0.009 0.051 0.038 0.035 -0.006 0.054 0.044 0.037 1961 0.074 0.050 0.038 0.035 0.082 0.053 0.043 0.037 1962 0.025 0.055 -0.010 0.035 0.021 0.056 -0.002 0.036 1963 0.064 0.052 -0.029 0.034 0.074 0.055 -0.022 0.036 1964 -0.204 0.049 -0.051 0.034 -0.182 0.053 -0.045 0.036 1965 -0.103 0.049 -0.055 0.033 -0.104 0.053 -0.050 0.036 1966 -0.035 0.051 -0.079 0.032 -0.035 0.054 -0.074 0.034 1967 0.006 0.048 -0.020 0.031 -0.005 0.051 -0.020 0.033 1968 -0.056 0.046 0.005 0.029 -0.042 0.049 0.009 0.031 1969 0.087 0.046 -0.008 0.028 0.089 0.049 -0.003 0.030 1970 0.023 0.046 -0.011 0.028 0.038 0.048 -0.004 0.030 1971 -0.099 0.047 0.022 0.027 -0.097 0.050 0.027 0.029 1972 -0.009 0.047 -0.017 0.026 -0.006 0.049 -0.017 0.028 1973 0.108 0.042 -0.033 0.026 0.110 0.045 -0.037 0.027 1974 -0.110 0.044 -0.046 0.025 -0.131 0.046 -0.050 0.027 1975 -0.056 0.045 -0.018 0.025 -0.060 0.048 -0.025 0.027 1976 -0.164 0.046 -0.038 0.025 -0.162 0.048 -0.046 0.026 1977 0.133 0.042 0.002 0.023 0.117 0.044 0.002 0.024 1978 0.005 0.042 0.056 0.022 0.005 0.044 0.053 0.023 1979 0.093 0.031 0.141 0.021 0.110 0.032 0.130 0.022 1980 0.212 0.034 0.122 0.022 0.196 0.036 0.116 0.023 1981 0.259 0.038 0.168 0.022 0.220 0.040 0.161 0.023 1982 0.042 0.040 0.164 0.023 0.050 0.042 0.149 0.024 1983 0.235 0.039 0.132 0.023 0.228 0.041 0.119 0.025 1984 0.069 0.036 0.102 0.024 0.050 0.038 0.093 0.025 1985 0.056 0.032 0.142 0.023 0.047 0.033 0.128 0.025 1986 0.108 0.033 0.152 0.024 0.090 0.035 0.135 0.025 1987 0.242 0.033 0.172 0.025 0.228 0.035 0.155 0.026 1988 0.287 0.034 0.234 0.026 0.261 0.036 0.213 0.028 1989 0.169 0.036 0.281 0.028 0.149 0.039 0.256 0.029 1990 0.361 0.038 0.264 0.029 0.336 0.040 0.243 0.031 1991 0.344 0.040 0.245 0.031 0.308 0.042 0.225 0.033 1992 0.159 0.041 0.260 0.033 0.159 0.044 0.244 0.035 1993 0.191 0.043 0.266 0.035 0.173 0.046 0.245 0.037 1994 0.246 0.045 0.256 0.036 0.241 0.047 0.229 0.038 1995 0.390 0.045 0.311 0.036 0.343 0.047 0.279 0.038 1996 0.293 0.043 0.391 0.037 0.226 0.046 0.351 0.039 1997 0.437 0.042 0.413 0.038 0.413 0.045 0.364 0.040 1998 0.589 0.046 0.408 0.039 0.533 0.049 0.359 0.041 1999 0.355 0.047 0.452 0.040 0.306 0.050 0.409 0.042 2000 0.367 0.048 0.482 0.041 0.317 0.050 0.433 0.044 2001 0.509 0.047 0.478 0.042 0.474 0.050 0.432 0.044 2002 0.588 0.046 0.502 0.042 0.533 0.049 0.463 0.044 2003 0.572 0.047 0.559 0.042 0.531 0.050 0.516 0.044 2004 0.474 0.045 0.579 0.042 0.461 0.047 0.525 0.044 2005 0.654 0.046 0.585 0.041 0.583 0.049 0.525 0.044 2006 0.607 0.046 0.567 0.041 0.517 0.048 0.505 0.043 2007 0.615 0.044 0.595 0.041 0.535 0.046 0.521 0.043 2008 0.483 0.043 0.601 0.040 0.432 0.045 0.525 0.043 2009 0.616 0.042 0.594 0.040 0.540 0.045 0.517 0.042 2010 0.685 0.043 0.587 0.040 0.601 0.046 0.512 0.042 2011 0.569 0.043 0.612 0.040 0.478 0.045 0.538 0.042 2012 0.582 0.045 0.623 0.040 0.509 0.046 0.553 0.043 2013 0.610 0.044 0.649 0.040 0.563 0.047 0.586 0.043 2014 0.671 0.045 0.725 0.041 0.616 0.048 0.658 0.043 2015 0.810 0.044 0.775 0.041 0.762 0.046 0.704 0.043 2016 0.949 0.046 0.807 0.041 0.839 0.047 0.725 0.043 2017 0.833 0.046 NaN NaN 0.741 0.048 NaN NaN 2018 0.774 0.044 NaN NaN 0.667 0.046 NaN NaN