Global annual to decadal climate update

General Studies Paper 3

Context: Recently, the World Meteorological Organization (WMO) issued the Global Annual to Decadal Climate Update.

About Global Annual to Decadal Climate Update

• It is produced annually in May and summarizes the predicted future of the global climate over the next year and the next five years.
• The focus is on climate indices such as global mean near-surface temperature, Atlantic multidecadal variability, and the El Niño/Southern Oscillation, as well as regional indices and annual and multi-year seasonal means of near-surface temperature, mean sea-level pressure, and precipitation.

Findings 

• Global temperatures are likely to surge to record levels in the next five years, fuelled by heat-trapping greenhouse gases and a naturally occurring El Niño event. 
  • The annual mean global near-surface temperature for each year between 2023 and 2027 is predicted to be between 1°C and 1.8°C higher than the 1850-1900 average.
    • This is used as a baseline because it was before the emission of greenhouse gases from human and industrial activities.
  • There is a 66% chance that the annual average near-surface global temperature between 2023 and 2027will be more than 1.5°C above pre-industrial levels for at least one year.
  • There is a 98% chance that at least one of the next five years, and the five-year period as a whole, will be the warmest on record.
  • Arctic warming is disproportionately high.
    • Compared to the 1991-2020 average, the temperature anomaly is predicted to be more than three times as large as the global mean anomaly when averaged over the next five northern hemisphere extended winters.
  • Predicted precipitation patterns for the May to September 2023-2027 average, compared to the 1991-2020 average, suggest increased rainfall in the Sahel, northern Europe, Alaska, and northern Siberia, and reduced rainfall for this season over the Amazon and parts of Australia.

Implications 

• A warming El Niño is expected to develop in the coming months and this will combine with human-induced climate change to push global temperatures into uncharted territory.
• In addition to increasing global temperatures, human-induced greenhouse gases are leading to more ocean heating and acidification,sea ice and glacier melt, sea level rise, and more extreme weather.
• This will have far-reaching repercussions for health, food security, water management, and the environment.

Way Ahead 

• This report does not mean that we will permanently exceed the 1.5C specified in the Paris Agreement, which refers to long-term warming over many years.
• However, WMO is sounding the alarm that we will breach the 1.5C level on a temporary basis with increasing frequency.
• There is a need to strengthen weather and climate services to support climate change adaptation.
• The focus should be on the ongoing Early Warnings for All initiative to protect people from increasingly extreme weather