The world witnessed a record increase in greenhouse gas concentrations, sea-level rise, ocean heat and ocean acidification in 2021, triggering extreme weather events and adversely impacting the lives of more than two billion people, said a report released by the UN's World Meteorological Organization (WMO).

Concentration carbon dioxide (CO2), a greenhouse gas known for warming the climate, reached 413.2 parts per million (ppm) globally, or 149 percent of the pre-industrial level. The excessive increase in the emissions has led to acidification of oceans, responsible for absorbing nearly 23 percent of CO2 emitted by human activities, said the WMO State of the Global Climate Report 2021 released on Wednesday.

According to WMO, this annual report gives details of climate indicators such as temperatures, ocean heat, ocean acidification, sea level rise, sea ice glaciers and extreme weather. It also has a section devoted to impacts on sustainable development, food security, displacement and ecosystems.

In the previous temporary report released on May 9, 2022, the annual mean global near-surface temperature for each year between 2022 and 2026 is predicted to be between 1.1 and 1.7 degrees Celsius higher than pre-industrial levels (the average over the years 1850-1900). The temporary report also pointed out that there is a 50 percent chance of the annual average global temperature temporarily reaching the 1.5-degree threshold above the pre-industrial level for at least one of the next five years.

The global mean sea level increased at an average of 4.5 mm per year from 2013 to 2021, more than double the rate between 1993 and 2002. According to the report, accelerated loss of ice mass from the ice sheets significantly contributes to the rising sea level. Such an alarming rise impacts the lives of millions of coastal dwellers and increases their vulnerability to tropical cyclones.

"The heat trapped by human-induced greenhouse gases will warm the planet for many generations to come," warned Petteri Taalas, secretary-general, WMO. "Some glaciers have reached the point of no return, and this will have long-term repercussions in a world in which more than two billion people already experience water stress."

The Global South faces one of the worst impacts of the warming climate. The Horn of Africa reels under drought, South Africa witnesses frequent floods and India and Pakistan struggles with severe heatwaves.

The report released ahead of the World Economic Forum 2022 Annual Meeting seeks to get the attention of global leaders toward meeting the climate targets. More than 2,000 leaders and experts from around the world are gathering at the WEF meeting under the theme, "History at a Turning Point: Government Policies and Business Strategies."

The report's key findings will also be used during the annual UN Climate Change negotiations known as COP27 in Egypt later this year.

The UN Secretary-General, António Guterres, in a video message, proposed five critical actions to jump-start the renewable energy transition. He suggested greater access to renewable energy technology and supplies, a tripling of private and public investments in renewables and an end to subsidies on fossil fuels which amount to roughly $11 million per minute.

"Renewables are the only path to real energy security, stable power prices and sustainable employment opportunities. If we act together, the renewable energy transformation can be the peace project of the 21st century," said Guterres.

He added that the world must act in this decade to prevent ever-worsening climate impacts and keep the temperature increase to below 1.5 degrees Celsius above pre-industrial levels.

(Cover: Residents sleep on a building pavement, to escape heat and frequent power outage in their residence area Karachi, Pakistan. /Reuters)