Five years ending 2019 set to be the hottest ever: UN Report
A day before the UN Climate Action Summit in New York, the UN Science Advisory Committee sounded alarm bells by revealing that average global temperature is already 1.1°C above pre-industrial times and 0.2°C warmer than 2011-2015 period.
The report , United in Science, which sums up latest climate science by top global research organisations including the World Meteorological Organisation said average global temperature for the 2015-2019 period is on track to be the warmest on record.
The global mean sea level rise increased from 3.04 millimetres per year in 1997-2006 to 4 mm/yr in 2007–2016.
Heatwaves were also the deadliest in the 2015–2019 period, affecting all continents and setting many new national temperature records.
World Health Organisation said that in 2000-2016, the number of people exposed to heatwaves was estimated to have increased by around 125 million. The average length of individual heatwave events was 0.37 days longer, compared to the period between 1986 and 2008.
It’s now increasingly becoming obvious that human-induced climate change is causing the rise in extreme weather events, said the 28 page report.
“Recent examples include confirmation that a slowdown of the jet stream – fast moving winds in the upper atmosphere - was directly related to record-breaking heatwaves across North America, Europe and Asia in 2018 and 2019, and that a series of extreme rainfall events were connected, despite being thousands of kilometres apart, and were also linked to the jet-stream pattern,” the report said.
Medium and low-income countries with an annual average temperature of 25 degree C will see the worst impacts on their economies, it added.
Quoting the International Monetary Fund, the report said for such countries “the effect of a 1 °C increase in temperature is a fall in growth by 1.2%.
Countries whose economies are projected to be hard hit by an increase in temperature accounted for only about 20% of global Gross Domestic Product in 2016. But they are home to nearly 60% of the global population, and this is expected to rise to more than 75% by the end of the century.”
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