El Niño likely to lose steam

The El Niño weather pattern is likely to transition into ENSO-neutral conditions in the next month or two, a US government weather forecaster said.

ENSO-neutral refers to those periods in which neither El Niño nor La Niña is present, according to the National Weather Service’s Climate Prediction Center (CPC).

The ENSO-neutral conditions are expected to continue through the northern hemisphere fall and winter, the CPC said in its monthly forecast.

“During June, El Niño was reflected in the continued presence of above average sea surface temperatures (SSTs) across the central equatorial Pacific Ocean. However, SST anomalies across most of the eastern Pacific decreased during the month,” the weather forecaster added.

Last month, it had pegged the chances of the El Niño weather pattern continuing through the fall and winter a bit lower at 50-55 per cent.

What is El Niño?

El Niño is a term for the warming phase of the El Niño Southern Oscillation (ENSO), a cyclical weather pattern that influences temperature and rainfall across the global. It is a warming of the central to eastern tropical Pacific Ocean. During an El Niño event, sea surface temperatures across the Pacific can warm by 1-3 degrees C or more for anything between a few months to two years.

El Niño impacts weather systems around the globe, triggering predictable disruptions in temperature, rainfall and winds.

La Niña is the opposite - a cooling phase of ENSO that tends to have global climate impacts opposite to those of El Niño.

El Niño events are not caused by climate change - they are a natural phenomenon that have been occurring for thousands of years.

El Niño and La Niña can make extreme weather events more likely in certain regions, including droughts, floods and storms.

The warmest year on record was 2016, which was a result of a powerful El Niño combined with long-term climate change.

According to the UN Office for the Coordination of Humanitarian Affairs (UNOCHA), more than 60 million people were impacted by the 2015-16 El Niño, although an exact number is hard to pinpoint.

East Africa, Southern Africa, the Pacific Islands, South East Asia and Central America were most affected by extreme weather, including below-normal rains and flooding.

The humanitarian fallout in certain areas included increased food insecurity due to low crop yields and rising prices, higher malnutrition rates, devastated livelihoods and forced displacement.

Excessive rainfall also triggered and exacerbated outbreaks of waterborne diseases such as cholera and typhoid as well as vector-borne diseases such as malaria.

How does El Niño affect India?

In April, the India Meteorological Department (IMD) forecast indicated that El Niño conditions could affect the monsoon in the first half.

According to weathermen, June ended with a 33 per cent deficit in monsoon rainfall across the country.

However, the southwest monsoon is likely to get a big boost as the El Niño phenomenon, which dries up the weather in India, has waned while positive changes in temperature in the Indian Ocean are likely to support rainfall.

Barry makes landfall in Louisiana

Tropical storm Barry buffeted the US state of Louisiana on July 14, bringing more heavy rain and possible tornadoes to the region even as it weakened.

After briefly becoming the first hurricane of the Atlantic season, Barry was downgraded to a tropical storm following the landfall on July 13.

While there were few indications yet of widespread flooding, Louisianans kept a wary eye on several rivers and canals being pushed to their limits by the torrential rainfall and by flooding upstream.

Rain fell in New Orleans, the state’s biggest city, but there was little wind. Thousands of people had abandoned their homes and tens of thousands lost power.

Fears that the levee system protecting New Orleans could be compromised eased after the Army Corps of Engineers voiced confidence that it would hold, but Mayor LaToya Cantrell urged residents not to be complacent.

What’s in a name?

Hurricane, cyclone and typhoon are different terms for the same weather phenomenon: torrential rain and maximum sustained wind speeds (near centre) exceeding 119 km per hour.

* In the western North Atlantic, central and eastern North Pacific, Caribbean Sea and Gulf of Mexico, such a weather phenomenon is called a hurricane.

* In the western North Pacific, it is called a typhoon.

* In the Bay of Bengal and Arabian Sea, it is called a cyclone.

* In the southwest Indian Ocean, it is called a tropical cyclone.

The typhoon season in the western North Pacific region typically runs from May to November. The Americas/Caribbean hurricane season runs from June 1 to November 30, peaking in August and September. The cyclone season in South Pacific and Australia normally runs from November to April. In the Bay of Bengal and Arabian Sea, tropical cyclones usually occur from April to June, and September to November. The east coast of Africa normally experiences tropical cyclones from November to April.

Meteorologists around the world use modern technology such as satellites, weather radars and computers, etc. to track tropical cyclones as they develop. Tropical cyclones are often difficult to predict, as they can suddenly weaken or change their course.

The World Meteorological Organisation framework allows the timely and widespread dissemination of information about tropical cyclones. As a result of international cooperation and coordination, tropical cyclones are increasingly being monitored from their early stages of formation.