Story highlights Despite having La Niña, 2018 was 4th warmest year

20 hottest years have all occurred since 1997

Warming is worsening world hunger

Unprecedented heat and drought on multiple continents

(CNN) Another day, another alarming report about how climate change is not a future problem but rather one that is having severe effects all over the planet now.

This time, the report comes from the World Meteorological Organization , an intergovernmental organization of 191 national meteorological services, such as the US National Weather Service, the UK Met Office and the Australian Bureau of Meteorology.

The past four years have the been the hottest on record, going back to 1850, the report says, with the 20 hottest years on the list all occurring in the past 22 years.

Global average temperatures from five independent datasets. The chart shows the overall warming trend since the beginning of the last century, accelerating in the past several decades.

Global temperatures for January through October of this year have been 0.98 degrees Celsius (1.8 degrees Fahrenheit) above the pre-industrial average from 1850-1900 (the period before human-emitted greenhouse gases accumulated in the atmosphere to the point at which they began warming the planet).

2018 was not as hot as the previous three years, owing to the presence of La Niña, a cooling of the tropical waters in the Pacific Ocean that tends to bring down the global temperature; 2015 and 2016 had a strong El Niño that added to the globe's warming trend.