At the Paris Agreement, nations pledged to cut emissions and avoid dangerous temperature rises. Yet, the rise in greenhouse gas levels and temperatures appears to be accelerating.
Record growth of carbon dioxide levels at Mauna Loa
Annual mean carbon dioxide level measured at Mauna Loa, Hawaii, grew by 3.17 ppm (parts per million) in 2015, a higher growth rate than in any year since the record started in 1959.
At higher northern latitudes, carbon dioxide levels are higher than elsewhere on Earth, as illustrated by above image. These high greenhouse gases contribute to accelerated warming of the Arctic.
Methane levels rising even faster than CO2 levels, especially over Arctic Ocean
As above image illustrates, the mean level of 1839 ppb that was reached on September 7, 2014, is some 263% of the ~700 ppb that historically was methane's upper level.
The image below, from an earlier post, shows the available World Meteorological Organisation (WMO) annual means, i.e. from 1984 through to 2014, with added polynomial trendline based on these data. The square marks a high mean 2015 level, from NOAA's MetOp-2 satellite images, and it is added for comparison, so it does not influence the trendline, yet it does illustrate the direction of rise of methane levels and the threat that global mean methane levels will double well before the year 2040.
Global mean temperature in 2015 was 0.87°C (~1.6°F) higher than in 1951-1980.
Above image shows NASA data with a polynomial trendline added that points at a 2015 temperature that is more than 1.1°C (~2.03°F) higher than it was in 1900.
Additionally, some 0.3°C warming had already taken place by the year 1900, as discussed in an earlier post.
Together, that makes that 2015 temperatures were 1.47°C above pre-industrial levels.
Furthermore, temperatures did rise steeply over the course of the year 2015.
By the end of the year 2015, the temperature rise was even stronger than the average for 2015 would indicate, as illustrated by the image on the right.
It is now 2016 and temperatures are still rising. In other words, it now is more than 1.5°C or 2.7°F warmer than in pre-industrial times. In conclusion, we have already crossed the 1.5°C guardrail that the Paris Agreement had pledged to try and limit global warming to.
feedbacks such as disruption of the jet stream and methane eruptions from the seafloor of the Arctic Ocean.
The image below shows that, when that same trendline featuring in above graph is extended into the future, it points at a 2°C or 3.6°F global temperature anomaly rise before the year 2030, a rise of about 4°C or 7.2°F by 2040, and a 10°C or 18°F rise before the year 2060. That would be a rise compared to the period 1951-1980, i.e. warming compared to pre-industrial levels would be even more severe.
Three points are important to help more fully grasp the predicament we are in:
- At higher latitudes of the Northern Hemisphere, temperatures are rising faster than globally, as illustrated by above image that shows that a 10°C rise could hit the Arctic by 2030.
- Summer peaks will be even more devastating than annual averages.
- The rise of temperatures on land will be steeper than the rise in the combined land-ocean temperatures, as illustrated by the image below that shows that a 3°C rise on land could occur well before the year 2030.
Comprehensive and effective action needed
As greenhouse gases and temperatures keep rising, the heat will be felt earliest and most severely on land, during the northern summer and in the Arctic.
One big danger is that soil that was previously frozen will become exposed and will start releasing huge amounts of carbon, in the form of carbon dioxide or methane.
Furthermore, boreal forest, tundra and peat bogs are at risk of firestorms that will also come with huge amounts of emissions.
All this will make the rise in temperature speed up even more, with much of the soot from firestorms in Siberia settling on the Himalaya Tibetan plateau, melting the glaciers there and causing short-term flooding followed by rapid decrease of the flow of ten of Asia’s largest river systems that originate there, with more than a billion people’s livelihoods depending on the continued flow of this water.
Again, the reason why temperatures look set to rise so abruptly and dramatically in the Arctic is feedbacks, as discussed as the feedbacks page. The biggest danger that comes with these rapidly rising temperatures in the Arctic is that large methane eruptions from the seafloor of the Arctic Ocean will further heat up the atmosphere, at first in hotspots over the Arctic, and eventually around the globe, while also causing huge temperature swings and extreme weather events, further contributing to increasing depletion of fresh water and food supply.