2015-2018 become the hottest in the history of meteorological observations
And 2018 took fourth place in the list of hottest years.
The last four years were the hottest on Earth in the entire history of observations. 2018 took fourth place in the list of the hottest.
Scientists have processed the data from 6,300 weather stations in different places of the planet, taking into account the effect of higher heat generation in the different cities and the distance between stations. It is possible to avoid errors caused by local reasons or incorrect extrapolation of the data, but even with all the errors (plus or minus 0.07 degree Celsius), the researchers ‘ conclusions are unambiguous: the average annual temperature in 2018, averaged over the entire planet, was 0.83 ℃ higher than the same indicator in the period from 1951 to 1980, according to NASA, and 0.79 ℃ — according to NOAA.
Data from different meteorological services give slightly different results due to the fact that scientists have access to different weather stations and may use different algorithms for calculation of averages (as noted above, the standard formula to “add up and divide by the number of observations” would not do stations in cities will increase global temperature). However, these differences are manifested in the divergence within a couple tenths of a degree.
For getting four years in the list of the hottest affected by two phenomenon.
The first (but not the most important) was the El Nino, a cyclical process in the South Pacific ocean with a period of several years. When El niño is changing the nature of ocean currents, the water becomes warmer and dry period on the coast of South America gives way to the monsoons. Peak temperatures occurred in the year 2016, which just became the hottest in history. The second, more important reason is global warming, which continues due to the increase in carbon dioxide emissions.
If humanity can reduce emissions of carbon dioxide, the temperature increase by the end of the twenty-first century will be about two degrees. A more realistic growth scenario assumes three degrees, can have disastrous consequences from indisputable increase in Global sea level with flooding of coastal areas before a possible weakening of a number of ocean currents including the Gulf stream. In the latter case, the average temperature in Europe likely will decline, which, however, does not cancel the General increase in planetary scale. Detailed prediction of the effects of global warming — extremely difficult task, but the fact of the growth temperatures for today are undeniable, and the connection of this warming to anthropogenic emissions is supported by most researchers.