Corona-induced CO2 emission reductions are not yet detectable in the atmosphere
To reach the Paris climate goals, decade-long measures are needed

Date:
September 21, 2020
Source:
Karlsruher Institut fu"r Technologie (KIT)
Summary:
The impact of the corona pandemic will reduce worldwide carbon
dioxide emissions by up to eight percent in 2020. Cumulative
reductions of about this magnitude would be required every year to
reach the goals of the Paris Agreement by 2030. Measurements now
revealed that concentration of carbon dioxide in the atmosphere
has not yet changed due to the estimated emission reductions.



FULL STORY ========================================================================== Based on current data measured in the energy, industry, and mobility
sectors, restrictions of social life during the corona pandemic can be predicted to lead to a reduction of worldwide carbon dioxide emissions
by up to eight percent in 2020. According to the Intergovernmental
Panel on Climate Change (IPCC), cumulative reductions of about this
magnitude would be required every year to reach the goals of the Paris Agreement by 2030. Recent measurements by researchers of Karlsruhe
Institute of Technology (KIT) revealed that concentration of carbon
dioxide (CO2) in the atmosphere has not yet changed due to the estimated emission reductions. The results are reported in Remote Sensing (DOI: 10.3390/rs12152387).


==========================================================================
The corona pandemic has changed both our working and our private
lives. People increasingly work from home, have video conferences instead
of business trips, and spend their holidays in their home country. The
lower traffic volume also reduces CO2 emissions. Reductions of up to
eight percent are estimated for 2020. "In spite of the reduced emissions,
our measurements show that CO2 concentration in the atmosphere has not
yet decreased," says Ralf Sussmann from the Atmospheric Environmental
Research Division of KIT's Institute of Meteorology and Climate Research (IMK-IFU), KIT's Campus Alpine, in Garmisch- Partenkirchen. "To reduce
CO2 concentration in the atmosphere in the long run, restrictions imposed during the corona pandemic would have to be continued for decades. But
even this would be far from being sufficient." To prove this, researchers additionally studied a long-term scenario that can be controlled well
with atmospheric measurements: The goal of the Paris Climate Agreement
to limit global warming to 1.5 degrees Celsius can only be reached by an immediate significant reduction of CO2 emissions and a further decrease
down to zero by 2055. "The restrictions imposed during the corona crisis, however, are far from being sufficient. They have just resulted in a
one-time reduction by eight percent. To reach zero emissions in the coming decades, cumulative reductions of the same magnitude would be required
every year, i.e. 16 percent in 2021, 24 percent in 2022, and so on. For
this, political measures have to be taken to directly initiate fundamental technological changes in the energy and transport sectors," Sussmann says.

For the study, the team used data from the Total Carbon Column Observing Network (TCCON). It measured the concentrations in different layers of
the atmosphere above Garmisch-Partenkirchen and at other places around
the globe.

"High-tech infrared spectrometers are applied, which use the sun as a
light source. The measurement method is highly precise, uncertainties
are in the range of a few thousandths," Sussmann adds.

Long Life of CO2 Prevents Early Detection According to the researchers,
the long life of CO2 and the high background concentrations that have accumulated since the start of industrialization prevent the changes
in the atmosphere from being detected. "But also natural impacts make
early detection difficult: Anthropogenic emissions, the main cause of
the long-term increase in atmospheric CO2, are superposed by annual fluctuations of the growth rate due to natural climate variabilities
of ocean sinks and land vegetation," Sussmann says. Successful emission reduction, hence, is hard to detect by atmosphere measurements.

For their study, the researchers compared the TCCON measurements with
the prognoses of the atmospheric growth rate for 2020 - with and without
corona restrictions. "Precision analysis of atmosphere measurements
revealed that the impacts of COVID-19 measures on the atmosphere might
be measured after little more than six months, if the reference state
without COVID-19 would be predicted precisely," the climate researcher explains. "In any case, we would be able to find out within presumably
two and half years, whether global political and social measures will
help us find viable alternatives of fossil fuels and reach the goals of
the Paris Climate Agreement."

========================================================================== Story Source: Materials provided by
Karlsruher_Institut_fu"r_Technologie_(KIT). Note: Content may be edited
for style and length.


========================================================================== Journal Reference:
1. Ralf Sussmann, Markus Rettinger. Can We Measure a COVID-19-Related
Slowdown in Atmospheric CO2 Growth? Sensitivity of Total Carbon
Column Observations. Remote Sensing, 2020; 12 (15): 2387 DOI:
10.3390/rs12152387 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/09/200921102540.htm

--- up 4 weeks, 6 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)