UN warns: increased risk of heatwave, drought and floods worldwide

The United Nations (UN) is warning that the El Niño climate phenomenon, already established in the tropical Pacific Ocean, will intensify rapidly and could reach a high level of intensity between July and September. According to the World Meteorological Organization (WMO), the evolution of this phenomenon will increase the risk of heat waves, severe droughts, torrential rainfall and other extreme weather phenomena in many regions of the world, reports AFP.

• El Niño could reach a high level of intensity

In its latest seasonal climate bulletin, the World Meteorological Organization shows that the El Niño phenomenon has already established itself in the tropical Pacific and is expected to intensify rapidly in the coming months. According to WMO estimates, the episode will reach a high level of intensity between July and September, corresponding to level 3 on a four-step scale used by specialists to assess the phenomenon. The report complements the warning issued by the WMO in early June about the imminent establishment of El Niño. Later, on 11 June, the US National Oceanic and Atmospheric Administration (NOAA) confirmed that the phenomenon began in May and is expected to reach its peak intensity towards the end of this year.

• The phenomenon changes the climate on a global scale

El Niño is a natural climate phenomenon that generally occurs once every two to seven years and persists for between nine and 12 months. It causes the waters of the central and eastern equatorial Pacific to warm, changing atmospheric circulation and influencing the precipitation and temperature regimes around the globe. According to the WMO, its effects on the global average temperature are usually stronger in the year following the phenomenon's establishment. "El Niño is already present and is expected to intensify rapidly, reaching high intensity," said WMO Secretary-General Celeste Saulo.

The official warned that the evolution of the phenomenon will increase the likelihood of droughts, heavy rains, and heat waves both on land and in the marine environment.

• After the climate records of 2023-2024, a new episode raises concerns

The last major episode of El Niño, held in the period 2023-2024, contributed to the recording of the highest global temperatures observed to date.

Specialists point out that the phenomenon does not generate global warming on its own, but it amplifies the trend of increasing temperatures caused by climate change and favors the occurrence of extreme weather events. An example is Peru, where authorities have already established a state of emergency in approximately 800 municipalities, due to the high risk of heavy rainfall associated with the El Niño phenomenon.

• Oceans continue to warm

According to the WMO, all major international climate prediction centers indicate a steady and significant increase in water temperatures in the central and eastern equatorial Pacific. Seasonal anomalies in sea surface temperatures are expected to exceed two degrees Celsius in the main monitored areas, and the high agreement between climate models provides a high level of confidence in these estimates. The organization estimates that the phenomenon will continue to intensify in the period September-November, extending its influence over an increasing number of regions. At the same time, temperatures in the equatorial Atlantic are forecast to remain generally above normal values.

• Different forecasts depending on the region

The WMO estimates that there is a very high probability that almost all populated regions of the planet, except for the polar regions, will record temperatures above climatological averages in the period July-September. In terms of precipitation, the organization anticipates above-normal rainfall in the central and eastern equatorial Pacific, while precipitation deficits are expected in parts of the tropical Indian Ocean, the Indian subcontinent and large areas of Australia. Equatorial Africa is expected to experience a contrasting evolution, with above-average precipitation in the northern Gulf of Guinea and below-normal values in the Horn of Africa. Deficits in precipitation are also forecast in the Caribbean, northwestern South America and parts of Central America, while the southwestern United States could benefit from wetter than usual conditions.

• Europe, between abundant precipitation in the south and deficit in the north

For the European continent, the WMO forecasts indicate a contrast between the north and the south. Thus, southern Europe could record precipitation amounts above the climatological average, while the north of the continent is expected to be drier than usual. However, the organization warns that the forecasts are The forecast for Europe is subject to a higher degree of uncertainty than for other regions of the world, so these estimates should be interpreted with caution. Overall, the new WMO report confirms that the strengthening of the El Niño phenomenon is overlapping with the global warming trend driven by greenhouse gas emissions, increasing the likelihood of extreme weather events and significant economic and social impacts in the coming months.