World average temperatures were the hottest in June and during the first six months of this year, according to climatologists. Arctic sea ice shrunk in June to the third smallest area on record.
Climate scientists warned Tuesday that a fresh El Nino oceanic phenomena emerging in Pacific Ocean waters off Peru is likely to foreshadow hotter planetary weather and lead to further new record highs.
The United States' National Oceanic and Atmospheric Administration (NOAA) said the world average temperature in June was 16.33 Celsius (61.48 Fahrenheit), an alarming one-quarter of a degree warmer than the previous record set in 2014.
In the past, records were broken by only one or two-hundredths of a degree, not one-quarter.
French Foreign Minister Laurent Fabius, tasked with steering UN talks in Paris toward a climate rescue pact in December, urged countries on Monday to "look now for compromise on the big political issues."
The UN has set the goal of limiting average global warming to two degrees Celsius over pre-industrial levels by switching to renewables over fossil energy sources.
Four record months
June was one of among four months in 2015 that each saw record average temperatures, based on measurements made since 1880. The other three months were February, March and May, according to the NOAA.
In addition, the first half of 2015 taken as a whole was one-sixth of a degree warmer at an average of 14.35 Celsius, compared to the old record set in 2010.
NOAA climatologist Jessica Blunden said if the emerging El Nino effect became stronger, then it would push average temperatures "off the charts."
"This is what anthropogenic [man-made] global warming looks like, just hotter and hotter," said Jonathan Overpeck, the co-director of the University of Arizona's environmental institute.
Blunden said broken global monthly heat records had occurred in 25 months since 2000. The last monthly cold record occurred in 1916.
Heatwaves in Pakistan, India
Pakistan's exceptional heatwave during June was blamed for the loss of more than 1,200 lives. In May, a heatwave n India claimed more than 2,000 lives. It ranked as India's fifth deadliest on record.
Exceptional heat has also gripped other parts of Asia as well as Australia, South America, Africa, western North America, Spain and Austria and parts of the Balkans.
Also Tuesday, the NOAA said that sea ice in the Arctic had been measured at 906,000 square kilometers (350,000 square miles), or 7.7 percent less than the average for the period 1981 to 2010.
"This was the third smallest June extent since records began in 1979," NOAA said.
Japan confirms figures
Clare Nullis, spokeswoman for the UN's World Meteorological Organization, said the record average temperatures, both on land and across ocean surfaces, were confirmed by the Japan Meteorological Agency's Tokyo Climate Center.
Nullis said a major concern was rising heat accumulation in the waters of world's oceans, which have so far acted as buffers.
Nullis said that according to readings from the Australian Bureau of Meteorology, the El Nino effect was likely to strengthen and persist into early 2016.
So far, heatwave data has corresponded to climate change model expectations, she added.
El Nino is a period when winds pile up a layer of warm, nutrient-poor surface water off Peru, accompanied by high air pressures over the western Pacific. South American fisheries suffer while Australia and Southeast Asia turn dry.
Its impacts around the world are complicated, with Europe less affected.
During Europe's heatwave earlier this month, Omar Baddour, who coordinates the UN's climate data monitoring program, said experts were still assessing the correlation between natural variability and climate change.
Stefan Rahmstorf, an oceanic and climate scientist at the Potsdam Institute for Climate Impact Research in Germany, was more emphatic, stressing that "man-made global warming greatly increases the number of such heatwaves."