People wade through a foot of water in St. Mark’s Square in Venice, Italy
In 2019, the seaside city of Venice, Italy, endured its worst floods in 50 years. Credit: Claudia Melchiorri, CC BY-SA 4.0

“The indications are crystal clear: Global heating is accelerating,” United Nations (UN) secretary-general António Guterres said at a 10 March briefing to release a new report on climate change.

The year 2019 is likely the second warmest in instrumental records, the past 5 years are the five warmest on record, and the past 10 years represent the warmest 10-year average on record, according to the report by the World Meteorological Organization (WMO), a specialized agency of the UN.

“The results of this report demonstrate that climate change is already very visible in various ways.”

Only 2016, which began with a strong El Niño, tops 2019 as the warmest year on record, according to the WMO Statement on the State of the Global Climate in 2019.

“The results of this report demonstrate that climate change is already very visible in various ways. More ambitious climate mitigation efforts are needed to keep the warming below 2°C by the end of the century,” WMO secretary-general Petteri Taalas stated in the report.

Preliminary data from some specific locations, including the Mauna Loa Observatory in Hawaii, indicate that levels of three greenhouse gases—carbon dioxide (CO₂), methane, and nitrous oxide—continued to increase in 2019, as they had in 2018, according to the report.

The ocean is feeling the heat as well. About 90% of the excess energy accumulating in the climate system due to increased levels of greenhouse gases is stored in the global ocean, the report states. In turn, this ocean heat content contributes more than 30% of the observed global mean sea level rise through the thermal expansion of seawater. In addition, marine heat waves accounted for an average of nearly 2 months of unusually warm temperatures over the global ocean. And the ocean’s absorption of about 23% of annual CO₂ emissions, as noted in the report for the decade 2009–2018, is adding to ocean acidification.

The report also focuses on climate change effects on extreme weather events and other impacts to society.

“Climate-related events already pose risks to society through impacts on health, food and water security as well as human security, livelihoods, economies, infrastructure and biodiversity. Climate change also has severe implications for ecosystem services,” the report stated.

A Pivotal Year

“We count the cost”—from climate change—“in human lives and livelihoods as droughts, wildfires, floods, and extreme storms take their deadly toll. We have no time to lose if we are to avert a climate catastrophe,” Guterres said at the briefing.

The year 2020 is “a pivotal year for how we address the climate emergency.”

He said that 2020 is “a pivotal year for how we address the climate emergency.” The world needs to aim its ambitions high at the upcoming UN climate change conference in Glasgow, Scotland, in November, Guterres noted.

He said all countries need to demonstrate that they will reach net zero emissions by midcentury and that 70 countries so far have announced they are committed to that goal. Guterres also called for developed countries to deliver on their commitment to mobilize billions of dollars a year in investments in renewables and green technologies, for there to be a price on carbon, and for an end to “the vast and wasteful subsidies for fossil fuels.”

Fighting Climate Change and Coronavirus

At the briefing, Guterres and Taalas said that while the coronavirus and climate change are both major concerns, climate change looms much larger.

“Both the coronavirus and climate change are very serious problems. Both require a determined response by governments, institutions like the UN, and a response by people, and both must be defeated,” Guterres said. “But they are very different in nature. One thing is a disease that we all expect to be temporary, and its impacts we also expect to be temporary. The other thing is climate change, which has been there for many years and which will remain with us for decades and require constant action.”

Guterres added that the UN is doing its best to contain and hopefully eliminate the coronavirus, but that “it is important that all the attention that needs to be given to fight this disease does not distract us from the need to defeat climate change, from the need to fight inequality, and from the need to address all the other problems that the world is facing.”

—Randy Showstack (@RandyShowstack), Staff Writer


Showstack, R. (2020), UN report: 2019 was likely the second-warmest year in recorded history, Eos, 101, Published on 11 March 2020.

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