Photo :webshot.

November 1, 2021

Andrew Campbell 

Seven Climate Indicators are used to describe the changing climate, according to a new report coordinated by the World Meteorological Organization (WMO), providing a global view of the climate. They include global mean surface temperature, global ocean heat content, state of ocean acidification, glacier mass balance, Arctic and Antarctic sea-ice extent, global CO2 mole fraction, and global mean sea level. They are used to monitor the domains most relevant to climate change, such as atmospheric composition, energy changes caused by the accumulation of greenhouse gases and other factors, and land, ocean, and ice responses.

According to the UN's WMO’s annual "The State of the Global Climate 2020" report, released on October 31, the last seven years from 2015 to 2021 are on track to be the warmest on record. Despite the cooling effect of the La Nina phenomenon, which lowered temperatures at the start of the year, the WMO predicted that 2021 would be the fifth to seventh warmest year on record, based on data from the first nine months of the year.

The data show that the global mean temperature for 2020 was around 1.2 degrees Celsius higher than pre-industrial levels, as stated in the report's 

Foreword by United Nations Secretary-General Antonio Guterres, implying that time is running out to meet the Paris Agreement's goals. This entails cutting global greenhouse gas emissions by 45 percent from 2010 levels by 2030, with the ultimate goal of reaching net zero emissions by 2050.

In 2020, climate-related disasters such as floods, droughts, and storms, as well as the COVID-19 pandemic, affected more than 50 million people. In 2019, nearly 690 million people, or 9% of the global population, were undernourished, with nearly 750 million, or 10%, facing severe food insecurity. Food insecurity is expected to worsen by 2030. As a result, WMO Secretary-General Professor Petteri Taalas urged in the report's Foreword that stabilizing global mean temperature at 1.5°C to 2°C above pre-industrial levels by the end of this century will necessitate aggressive reductions in greenhouse gas emissions, which must begin this decade.