Climate change is advancing relentlessly despite the COVID-19 pandemic, scientists warn

Greenhouse gas concentrations in the atmosphere are at record levels and continue to rise, and emissions, which were subtly reduced by COVID-19, are already returning to pre-pandemic levels, a new United Nations report says.

The Scientific Research United in Science, carried out by the World Meteorological Organization (WMO), the UN Environment Programme, the Intergovernmental Panel on Climate Change, UNESCO, and other international organizations, states that everything points to the five-year period 2016-2020 being the warmest in recorded history. a trend that will continue in the coming years.

In addition, it emphasizes that the world is far from meeting the objectives of the Paris Agreement to keep the increase in global temperature below 2 ° C above pre-industrial levels or, better yet, to limit it to 1.5 ° C.

“Our world remains far off course to meet the Paris Agreement’s goal of limiting global temperature rise to 1.5 degrees Celsius. If things continued as they are, we would rise 3 to 5 degrees above the pre-industrial level,” the UN Secretary-General warned during the presentation of the report.

António Guterres reiterated that short-term coronavirus lockdown measures are not a substitute for sustained climate action.

“The consequences of our inability to address the climate emergency are everywhere: extreme heat waves, fires, floods and devastating droughts. And these challenges are only going to get worse,” he added.

The report highlights the growing and irreversible impacts of climate change affecting glaciers, oceans, nature, economies and the living conditions of the population and often perceived in the form of water-related threats, such as drought episodes or river floods.

The study also highlights how COVID-19 has hampered the ability to monitor those changes through the global observing system.

“Greenhouse gas concentrations – already the highest level in three million years – have continued to rise. Meanwhile, large swaths of Siberia have suffered a prolonged and notable heat wave during the first half of 2020, something impossible except for human-caused climate change. This report shows that, although many aspects of our lives have been altered in 2020, climate change is advancing relentlessly,” WMO Secretary-General Professor Petteri Taalas said in the report.

The last time greenhouse gas concentration levels were so high was between 2.6 and 5.3 million years ago, in the Pliocene era, when there were trees at the South Pole and the sea level was about 20 meters higher.

“Whether we are addressing a pandemic or the climate crisis, it is clear that we need science, solidarity and decisive solutions. We have a choice: to continue as usual, which leads to more calamities; or we can use the recovery from COVID-19 to provide a real opportunity to put the world on a sustainable path,” the UN Secretary-General emphasized.

The main conclusions of United in Science

Concentrations of greenhouse gases in the atmosphere

Atmospheric concentrations of carbon dioxide have continued to rise to unprecedented records according to the World Meteorological Organization.

Reference stations in the WMO Global Atmosphere Watch network reported _CO2 concentrations of more than 410 parts per million (ppm) during the first half of 2020.

In July of this year, concentrations of 414.38 ppm and 410.04 ppm, respectively, were recorded at Mauna Loa (Hawaii) and Cape Grim (Tasmania) stations, compared to 411.74 ppm and 407.83 ppm in the same month in 2019.

The agency explains that the reduction in emissions as a result of the COVID-19 pandemic of this 2020 will have a very limited effect on the rate of increase of its atmospheric concentrations, given that these are the result of current and past emissions and the extremely long life of that gas.

“To stabilize climate change, emissions must decrease steadily until net emissions are zero,” he says.

Global _CO2 emissions

According to the Global Carbon Project, another organization that participated in the realization of the report, it is estimated that during the height of the confinement measures in early April 2020 there was a reduction in carbon emissions of 17%, an unprecedented fact.

Even so, the levels remained equivalent to those of 2006, a sign of the drastic increase experienced over the last 15 years and the constant dependence on fossil fuels for energy generation.

At the beginning of June 2020, daily global CO emissions₂ of fossil origin were again close to the levels of 2019, a year in which a record of 36.7 gigatons was reached, 62% more than those registered when the negotiations on climate change began in 1990.

It is estimated that, in 2020, _CO2 emissions will decrease by between 4% and 7% due to the confinement measures. The exact percentage of reduction will depend on the evolution of the pandemic and the responses of governments to the emergency.

In addition, global emissions from human activities of methane, another greenhouse gas, have continued to increase over the past decade. The report stresses that current CO2 and methane emissions are not compatible with the requirements to achieve the goals of the Paris Agreement.

Rising heat

The global average temperature for the period 2016-2020 is expected to be the warmest on record, about 1.1 °C above the pre-industrial average of 1850-1900.

Similarly, in the five-year period from 2020 to 2024, the probability that pre-industrial levels will be exceeded by at least 1,5 °C in at least one year is 24 %,

There is also a 70% chance that, over the next five years, there will be one or more months with a temperature at least 1.5°C above pre-industrial levels.

According to the WMO, in the last five years the extent of Arctic sea ice has been below average. In the period 2016-2019, the recorded loss of glacier mass exceeded the values of any previous five-year period since 1950. The speed of mean sea level rise on a global scale has increased over the past decade.

The most serious consequences have been due to extreme weather and climate events. In many of them, a clear footprint of human-induced climate change has been recognized.

The oceans and the cryosphere

The Intergovernmental Panel on Climate Change (IPCC) explains that human-caused global warming is affecting systems essential for life: from mountaintops to the depths of the oceans, causing an acceleration of sea level rise and entailing a succession of knock-on effects on ecosystems and people’s security.

Glaciers and ice sheets around the world have lost mass. Between 1979 and 2018, arctic sea ice extent has shrunk in each and every month of the year. The increase in forest fires and the abrupt melting of permafrost, as well as changes in the hydrology of the Arctic and mountains, have changed the frequency and intensity of disturbances suffered by ecosystems.

The IPCC stresses that oceans around the world have suffered an uninterrupted rise in temperature since 1970 and have absorbed more than 90% of the excess heat from the climate system.

Since 1993, the rate of ocean warming and thus the rate of heat absorption has more than doubled. The frequency of marine heat waves has doubled and now their duration, intensity and extent are greater, causing episodes of large-scale coral bleaching. The ocean has absorbed between 20 and 30% of total _{man-made CO2} emissions since the 1980s, and this has increased ocean acidification.

Since 1950 many marine species have moved in search of suitable habitats and altered their seasonal behaviors in response to warming oceans, changes in sea ice, and loss of oxygen.

In addition, global mean sea levels are rising and the acceleration observed in recent decades is due to the increasingly rapid rate of ice loss in the Greenland and Antarctic ice sheets, as well as the steady loss of glacier mass and the thermal expansion of the ocean. The rate of global mean sea level rise from 2006 to 2015 is 3.6 ± 0.5 mm per year, an unprecedented value compared to the last century.

Floods and droughts

According to the WMO, the consequences of climate change that are most strongly felt today are changes in hydrological conditions.

By 2050, the number of people at risk of being killed by overflowing rivers and glacial lakes will increase from 1200 million to 1600 million.

From the early to mid-2010s, some 1900 million people – 27% of the world’s population – lived in areas potentially subject to severe water shortages. By 2050, that number could rise to as many as 3 billion people.

In 2019, 12% of the world’s population drank water from unimproved and unsafe sources. More than 30% of the world’s population, some 2400 million people, live without access to any form of sanitation.

Climate change is expected to increase the number of regions with water stress and exacerbate water scarcity in those areas that already suffer from it.

The cryosphere, the ice-covered parts of the planet such as layers and glaciers, is an important source of fresh water for mountainous regions and areas downstream.

“It can be said with a high level of confidence that the melting of glaciers will reach its maximum on a global scale by the end of the twenty-first century at the latest. It is then expected to shrink worldwide, with implications for water reserves,” the WMO said.

Meltwater is water released by melting snow or ice, including glacial ice, tabular icebergs, and ice shelves over the oceans.

It is estimated that in Central Europe and the Caucasus the maximum level has already been reached, and that in the Tibetan plateau region it will be reached between 2030 and 2050. Since meltwater from snow cover, permafrost and glaciers in that region accounts for up to 45% of total river flow, the decrease in their volume will affect the amount of water available to 1700 million people.

The emissions gap

“Transformative measures can no longer be postponed if the goals of the Paris Agreement are to be achieved,” the United Nations Environment Programme warns in the report.

In 2019, the agency revealed that, in order to reach the goal of keeping global warming at 2°C, between 2020 and 2030 global emissions would have to be reduced each year by about 3%, and to reach the Paris Agreement target of keeping global warming at 1.5°C, average annual reductions of more than 7% would have to be achieved.

While it is still possible to close the emissions gap, urgent and concerted action is needed across countries and all sectors. A significant part of the short-term potential can be realised by scaling up existing policies that have been demonstrated to be effective, for example, in renewable energy and energy efficiency, low-carbon means of transport and phasing out coal, UNEP says.

Beyond the horizon of 2030, new technological solutions and a gradual change in consumption models at all levels are needed. But it should be noted that there are already viable solutions from the technical and economic point of view.

COVID-19, an obstacle to observing changes on Earth

The COVID-19 pandemic has had a significant impact on global observing systems, which in turn has affected the quality of forecasts and other meteorological, climate and oceanographic services, the report warns.

Between March and April, observations made from aircraft were reduced by an average of between 75 and 80%, and this undermined the degree of accuracy of the forecasts generated from weather models.

Since June, there has been only a slight recovery. Observations made at manual weather stations, particularly in Africa and South America, have also been greatly affected.

In addition, four studies on variables such as carbon, temperature, salinity and alkalinity of water at all ocean depths, which are conducted only once per decade, have been cancelled. Surface carbon measurements from ships, which allow us to know the evolution of greenhouse gases, have also been interrupted.

The commitment that is needed from the large carbon emitters

During the launch press conference, António Guterres assured that he is very actively involved, both with governments and civil society, with the aim of convincing large emitters, such as the United States, India and China, that it is absolutely crucial that they commit to carbon neutrality by 2050 and to reduce CO emissions.₂ by 45% by 2030.

“Without the big emitters, all the efforts that are made will be insufficient,” he said.

Guterres stressed, however, that it is important to note that there has been a very important positive movement in the private sector, banks, and major multinational corporations, as well as in certain states or cities.

“All these reasons make me believe that the pressure on the governments of the big emitters will sooner or later give results and that it will be possible to have a global commitment,” he said.

Source: UN News