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United in Science 2020 – Assessing the Latest Climate Research

2020 witnessed a brief and unprecedented decline in carbon dioxide (CO2) and nitrogen dioxide (NO2) emissions. Breathtaking images collected by NASA and the European Space Agency’s pollution monitoring satellites compared a pollution-blanketed China of January 2020 with a clear picture in February 2020. The 17% decrease in emissions was short-lived, however, and CO2 emissions are at record levels and continue to rise. Climate change will not stop for global crises like COVID-19, and the need to cut emissions and achieve carbon neutrality by 2050 is critical – the period from 2016-2020 is slated to be the warmest five years on record, and based on current trends the world is not on track to remain below Paris Agreement goals.

These statistics come from the multi-agency United in Science 2020 Report, which assesses the latest climate data from leading scientific organizations. United in Science, initiated in 2019, serves as both a global checkpoint and a projection tool for future trends. The report incorporates input from the Global Carbon Project (GCP), one of Future Earth’s 19 Global Research Projects. The GCP, also a research partner of the World Climate Research Programme, works to establish common knowledge surrounding the three main greenhouse gases: carbon dioxide (CO2), methane (NH4), and nitrous oxide (N2O). 

The World Meteorological Organization (WMO) coordinated the report with contributions from the Global Atmosphere Watch (GAW), the Intergovernmental Panel on Climate Change (IPCC), the UNESCO Intergovernmental Oceanographic Commission (UNESCO-IOC), the UN Environment Programme (UNEP), and the UK Met Office.

The data shows rising greenhouse gas concentrations, subsequent changes in glaciers, ice sheets, oceans, and the cryosphere, and the impact on economies and human livelihoods. The report also discusses the effects of COVID-19 on climate monitoring systems.  

According to GCP data, global CO2 emissions reached a record in 2019 at 36.7 Gigatonnes. While 2020 was somewhat of an anomaly – the GCP estimates that during peak confinement for COVID-19 in April 2020, CO2 emissions dropped 17 percent compared to mean daily global averages in 2019 – CO2 levels recovered mostly by June 2020.

While the global drop in emissions seems staggering, the GCP report notes that emissions during 2020’s peak confinement were equivalent to emissions in 2006, only 14 years ago. This comparison places the world’s steep emissions growth into perspective and awakens the world to its dangerous fossil-sourced energy reliance. 

While CO2 emissions growth has slowed in the last decade – 1% in the previous decade versus 3% annual growth during the 2000s – oil and natural gas emissions have continued to trend upward. The development of the oil and gas industries offsets a decline in coal emissions. Land-use changes such as deforestation, degradation, and reforestation also contributed to anthropogenic CO2 emissions, heightened in 2019 due to tropical fires. 

Anthropogenic impacts don’t stop at CO2 – potent atmospheric NH4 emissions continue to rise. The GCP estimates that 60% of NH4 emissions are anthropogenic-caused; agriculture and fossil fuels contributing equally. Unless emissions either peak or decline shortly, the world will be unlikely to meet temperature stabilization goals. 

According to the GAW, atmospheric CO2, NH4, and N2O concentrations continue to rise while CO2 concentrations reach a record of nearly 410 parts per million (ppm). Reflecting the GCP findings, GAW states that only through sustained reduction, and eventually net-zero emissions, will the world be able to stabilize its climate. 

The WMO finds that 2016-2020 is set to be the warmest five-year period on record, 1.1° C above pre-industrial times. The ocean is responding – the rate of sea-level rise continues to increase due to the loss of ice mass from ice sheets and the warming and subsequent expansion of the oceans. The sea-ice extent has declined since 1979, at a rate of decline of 13 percent per decade. Additionally impacted are freshwater resources – analysis of glacier mass changes in the European Alps, Scandinavia, and the Rocky Mountains find a one-meter water equivalent glacier ice loss per year. 

The frequency and intensity of high-impact events, such as heavier rainfall associated with tropical cyclones and drought, heatwaves, and wildfires, have increased. Many of these weather events are anthropogenic. Hurricane Harvey, east Africa’s 2016/17 drought, and wildfires in the Amazon, Australia, and the Arctic have brought significant economic damage and death, risks that are estimated to increase as the climate warms.

The IPCC reported Arctic permafrost temperatures at a record high, as well as worrying oceanic trends. Among these are the increased frequency of marine heatwaves, increased ocean acidity, and lower dissolved oxygen levels in the open ocean, leading to mass coral bleaching and large-scale shifts in ecosystem and species distributions. 

The world’s population is at risk – water is increasingly scarce in some regions, destructive or unsanitary in others. Global warming will further stress water-poor areas as snowpack, glaciers, permafrost, sea-ice and land-based ice sheets decline. 

UNEP, which issued an Emissions Gap Report, described their findings as “sobering” – the world is on track for an increase of 3.0 to 3.2 °C by the end of this century. The emissions gap, or the difference between where emissions are and where they need to be to meet Paris Agreement goals, is larger than ever. Transformational global changes can no longer wait. 

While the data looks disheartening, solutions are exact and time-sensitive. Decarbonization is now cheaper than ever, and renewable energy is the most affordable form of energy in most parts of the world. The prices of solar photovoltaic, offshore, and onshore wind continue to decline. 

The impacts of the COVID-19 pandemic go beyond emissions, as well. According to the WMO, oceanographic research vessels and commercial ships ceased to take data during the COVID-19 pandemic, and the GO-SHIP network canceled its decadal ocean survey. These data gaps will only heighten the importance of international coordination and data collaboration. 

Read the full report below: