Flagship UN study shows accelerating climate change on land, sea and in the atmosphere
A wide-ranging UN climate report, released on Tuesday, shows that climate change is having a major effect on all aspects of the environment, as well as on the health and wellbeing of the global population.
The report, The WMO Statement on the State of the Global Climate in 2019, which is led by the UN weather agency (World Meteorological Organization), contains data from an extensive network of partners.
It documents physical signs of climate change – such as increasing land and ocean heat, accelerating sea level rise and melting ice – and the knock-on effects on socio-economic development, human health, migration and displacement, food security, and land and marine ecosystems.
Australia’s 2018-2019 summer was the hottest ever recorded, reaching a peak of 41.9 degrees centigrade on December 18. Australia’s seven hottest days on record, and nine of the 10 hottest, occurred in 2019.
The country was not the only place affected by extreme heat, or wildfires. Heat records were broken in several European countries, including France, Germany, and the United Kingdom. Even Nordic countries saw record-breaking temperatures, including Finland, which registered a high of 33.2 degrees in the capital, Helsinki.
Several high latitude regions, including Siberia and Alaska, saw high levels of fire activity, as did some parts of the Arctic, where it was previously extremely rare. Indonesia and neighbouring countries had their the most significant fire season since 2015, and total fire activity in South America was the highest since 2010.
2020 has seen the warmest January recorded so far.
Greenhouse gas emissions continued to grow in 2019, leading to increased ocean heat, and such phenomena as rising sea levels, the altering of ocean currents, melting floating ice shelves, and dramatic changes in marine ecosystems.
The ocean has seen increased acidification and deoxygenation, with negative impacts on marine life, and the wellbeing of people who depend on ocean ecosystems. At the poles, sea ice continues to decline, and glaciers shrunk yet again, for the 32nd consecutive year.
In 2019, extreme weather events, some of which were unprecedented in scale, took place in many parts of the world. The monsoon season saw rainfall above the long-term average in India, Nepal, Bangladesh and Myanmar, and flooding led to the loss of some 2,200 lives in the region.
Parts of South America were hit by floods in January, whilst Iran was badly affected in late March and early April. In the US, total economic losses from flooding were estimated at around $20 billion. Other regions suffered a severe lack of water. Australia has its driest year on record, and Southern Africa, Central America and parts of South America received abnormally low rains.
2019 also saw an above-average number of tropical cyclones, with 72 in the northern hemisphere, and 27 in the southern hemisphere.
Following years of steady decline, hunger is again on the rise, driven by a changing climate and extreme weather events: over 820 million people were affected by hunger in 2018. The countries in the Horn of Africa were particularly affected in 2019, where the population suffered from climate extremes, displacement, conflict and violence. The region suffered droughts, then unusually heavy rains towards the end of the year, which was a factor in the worst locust outbreak in the past 25 years.
Greenland and Antarctica ice loss accelerating
Earth’s great ice sheets, Greenland and Antarctica, are now losing mass six times faster than they were in the 1990s thanks to warming conditions.
A comprehensive review of satellite data acquired at both poles is unequivocal in its assessment of accelerating trends, say scientists who studied 30 years of satellite images and data.
Between them, Greenland and Antarctica lost 6.4 trillion tonnes of ice in the period from 1992 to 2017.
This was sufficient to push up global sea-levels by 17.8mm. Of that combined 17.8mm contribution to sea-level rise, 10.6mm (60 %) was due to Greenland ice losses and 7.2mm (40%) was due to Antarctica.
The combined rate of ice loss for the pair was running at about 81 billion tonnes per year in the 1990s. By the 2010s, it had climbed to 475 billion tonnes per year.