Climate Trends1999: global temperature and CO₂
Anomaly+0.38 °C#33 / 146
CO₂368.54 ppm
Monthly values
| Month | Anomaly | CO₂ |
|---|---|---|
| January | +0.48 °C | 368.35 ppm |
| February | +0.64 °C | 369.28 ppm |
| March | +0.33 °C | 369.84 ppm |
| April | +0.32 °C | 371.15 ppm |
| May | +0.26 °C | 371.12 ppm |
| June | +0.36 °C | 370.46 ppm |
| July | +0.39 °C | 369.61 ppm |
| August | +0.31 °C | 367.06 ppm |
| September | +0.39 °C | 364.95 ppm |
| October | +0.34 °C | 365.52 ppm |
| November | +0.37 °C | 366.88 ppm |
| December | +0.40 °C | 368.26 ppm |
Temperature anomalies are in °C relative to the 1951–1980 average.
Method
Temperature: GISTEMP v4 Land-Ocean Temperature Index (global means), anomalies relative to 1951–1980 in °C; the annual value is NASA’s January–December mean. CO₂: NOAA GML monthly mean mole fraction at Mauna Loa in ppm; annual values are averages of the available months (only complete years are ranked). Recent values may be revised by the data providers.
About this page
In 1999 the global annual temperature anomaly was +0.38 °C and the mean CO₂ concentration at Mauna Loa was 368.54 ppm.