Tuesday, October 13, 2020

High Temperatures October 2020

September 2020 was the warmest September in the NASA record that goes back to 1880. In the image, September 2020 temperatures are compared to 1951-1980.

Global warming is accelerating

Similarly, Copernicus reports that September 2020 global surface air temperature was the highest September temperature on record. The image below shows temperatures averaged over the twelve-month period from October 2019 to September 2020.

Keep in mind that anomalies in the NASA image are compared to 1951-1980, while in the Copernicus image, anomalies are compared to the 1981-2010 average. Anomalies are even higher when compared to pre-industrial levels, as discussed further below.

The Copernicus image shows that the shape of the global anomaly over the past twelve months is very similar to the peak reached around 2016. This confirms that global warming is accelerating, because the peak around 2016 was reached under El Niño conditions, whereas current temperatures are reached under La Niña conditions and while sunspots are at a low, both of which are suppressing temperatures, as discussed in a recent post

What causes this acceleration of the temperature rise?

James Hansen and Makiko Sato confirm that global warming is accelerating and they explore whether this acceleration could be caused by fast feedbacks and short-term natural variability such as the sunspot solar cycle, which they give an amplitude of some 0.25 W/m². James Hansen and Makiko Sato conclude that global warming is accelerating due to a less negative atmospheric aerosol forcing.

Indeed, sunspots cannot explain this acceleration, because we're currently in a sunspot low. 

El Niño/La Niña cannot explain this acceleration either, because we're currently experiencing La Niña conditions, as also illustrated by above NOAA image

Further causes could be explored. As the image below shows, more than 90% of global warming currently goes into oceans. 

[ see also earlier post ]

The image below shows that high sea surface temperature anomalies feature on the Northern Hemisphere on October 22, 2020, with anomalies (from 1981-2011) as high as 10.2°C or 18.3°F (off the coast of North America). 

This is the more remarkable since, at the same time, low sea surface temperatures show up over the mid-Pacific, associated with La Niña. 

Stratification may cause oceans to take up less heat and the more heat will remain in the troposphere, the faster the temperature of the troposphere will rise, as discussed in an earlier post

As discussed under feedback #25 at the feedbacks page, the atmosphere can be expected to carry more water vapor as temperatures rise. Since water vapor is a potent greenhouse gas, more water vapor in the atmosphere will contribute to global warming. 

More evaporation also brings more heat into the atmosphere, as illustrated by the image on the right, and more heat will also be transferred to the atmosphere as the area of open water increases in the Arctic Ocean.

Further acceleration of the temperature rise

[ from earlier post ]
Further acceleration of global warming looks set to occur over the next few years as sunspot activity increases and as El Niño conditions will return. 

In 2019, Tiar Dani et al. analyzed a number of studies and forecasts pointing at the maximum in the upcoming Solar Cycle occurring in the year 2023 or 2024.

This analysis, discussed in a recent post, found some variation in intensity between forecasts, adding images including the one on the right, which is based on linear regression and suggests that the Solar Cycle 25 may be higher than the previous Solar Cycle 24. 

The need to transition to clean, renewable energy 

Fossil fuel and control over its supply is behind much of the conflict, violence and pollution that has infested the world for more than a century. Instead of continuing to use fossil fuel, the world must rapidly transition to using wind turbines, geothermal power, solar power, wave power, and similar ways to generate clean, renewable electricity.

This transition will remove much cause for conflict. Unlike fossil fuel, clean, renewable energy is available locally around the world and its use in one place doesn't exclude use of clean, renewable energy elsewhere.

This transition also comes with greater energy security and reliability, next to its numerous further benefits, e.g. it will make more land and water available for growing food and it will generate better and more jobs and investment opportunities, improve our health, and it will reduce greenhouse gas emissions. And, since it's more economic, the transition to clean, renewable energy will pay for itself as we go.

The more prices of solar panels, batteries, heat pumps, etc. keep falling, and the more urgency there is to act on climate change, the more sense it makes to transition to clean, renewable energy as soon as possible. Innovation has resulted in a huge drop in the cost of generating and storing clean, renewable electricity. In the Lazard 2019 analysis of the cost of energy and storage, the unsubsidized cost of solar PV (thin film utility scale) was $US32-42/MWh, i.e. already lower than the cost of fossil fuel and nuclear, which ranged from $US44-199/MWh. A recent tender for solar panels in Portugal received an offer equivalent to a price of $US13/MWh. 

Yet, while it makes sense from so many perspective and is absolutely necessary, this transition will not immediately lower temperatures, for a number of reasons. Maximum warming occurs about one decade after a carbon dioxide emission, so the full warming wrath of the carbon dioxide emissions over the past ten years is still to come, as discussed at the extinction page. Even with dramatic cuts in emissions, temperatures will not fall as long as levels of greenhouse gases in the atmosphere remain high. Additionally, sulfate cooling loss will further increase temperatures, as the world progresses with the necessary transition to the use of clean, renewable electricity. 

A rapid, steep temperature rise

The danger is that a rapid and steep temperature rise will be triggered by a combination of elements such as El Niño, sunspots, oceans taking up less heat and changes to aerosols such as further sulfate cooling loss. 

The potential for such a rapid, steep temperature rise is also illustrated by the image below, posted in February 2019 and showing a potential total rise of 18°C or 32.4°F from 1750 by the year 2026.

[ from earlier post ]

A rapid, steep temperature rise would be felt most strongly in the Arctic, causing albedo loss, emissions and transfer of heat from ocean to atmosphere that would all hit the Arctic most strongly, thus further speeding up the temperature rise, as also illustrated by the image below. 

As discussed in an earlier post, a rise of more than 5°C could happen within a decade, possible by 2026. Humans will likely go extinct with a 3°C rise and most life on Earth will disappear with a 5°C rise. 

[ from earlier post ]

Arctic Sea Ice

Meanwhile, temperatures in the Arctic have been very high, as illustrated by the image below showing air temperature in the Arctic up to October 12, 2020 (red line). 

For some time, Arctic sea ice exent has been at a record low for the time of year, as illustrated by the image below, showing the situation on October 20, 2020. 

For some time, sea ice area has also been at a record low for the time of year, as illustrated by the image below, showing the situation up to October 22, 2020.

Arctic sea ice volume has been very low, as illustrated by the image below showing volume up to September 30, 2020. 

As the image below shows, there was a lot of open water north of Greenland on October 23, 2020.

The image below, showing land outlines, is added for reference purposes. See also further images at this facebook post.

Temperatures can be expected to remain high. 

The image on the right shows a forecast for October 17, 2020, 21Z, run October 11, 2020 18Z. Very high temperatures are visible over the Arctic Ocean, while the Arctic as a whole shows an anomaly of 5.5°C compared to 1979-2000.

These high temperatures leave little or no opportunity for sea ice to build up thickness over the next few months, meaning there will be little or no buffer to consume incoming heat, as temperatures start to rise again early next year. 

Without such a buffer, a rapid temperature rise of the Arctic Ocean can be expected to take place, threatening to destabilize methane contained in sediments at the seafloor of the Arctic Ocean. 

The Methane Threat

As discussed repeatedly in earlier posts such as this one and as illustrated by the image below, from a recent post, methane levels are rising most strongly at higher altitudes. 

[ from earlier post ]

As discussed in a 2017 post, methane eruptions from the Arctic Ocean can be missed by measuring stations that are located on land and that often take measurements at low altitude, thus missing the methane that rises in plumes from the Arctic Ocean. Since seafloor methane is rising in plumes, it hardly shows up on satellite images at lower altitude either, as the methane is very concentrated inside the area of the plume, while little or no increase in methane levels is taking place outside the plume. Since the plume will cover less than half the area of one pixel, such a plume doesn't show up well at low altitudes on satellite images.

Over the poles, the Troposphere doesn't reach the heights it does over the tropics. At higher altitudes, methane will follow the Tropopause, i.e. the methane will rise in altitude while moving closer to the Equator.

Methane rises from the Arctic Ocean concentrated in plumes, pushing away the aerosols and gases that slow down the rise of methane elsewhere, which enables methane erupting from the Arctic Ocean to rise straight up fast and reach the stratosphere. Since little hydroxyl is present in the atmosphere over the Arctic, it is much harder for this methane to be broken down. 

What further makes the rise of methane at these high altitudes very worrying is that once methane does reach the stratosphere, it can remain there for a long time. The IPCC in 2013 (AR5) gave methane a lifetime of 12.4 years. The IPCC in 2001 (TAR) gave stratospheric methane a lifetime of 120 years, adding that less than 7% of methane did reach the stratosphere.


The situation is dire and calls for immediate, comprehensive and effective action, as described in the Climate Plan.


• Copernicus - Surface air temperature for September 2020

• NASA - Temperature anomalies September 2020

• September 2020 Global Temperature Update - by James Hansen

• Accelerated Global Warming (14 October 2020) - by James Hansen and Makiko Sato

• NOAA - Global monthly temperature anomalies, with ENSO status

• ENSO: Recent Evolution, Current Status and Predictions - NOAA, October 12, 2020

• Danish Meteorological Institute - Arctic temperature

• Climate reanalyzer

• Cryospherecomputing - by Nico Sun 

• Arctic sea ice extent - Vishop, Arctic Data archive System, National Institute of Polar Research, Japan 

• Portugal’s second solar PV tender sets new world record low price

• Lazard 2019 analysis of the cost of energy and storage 

• Temperatures threaten to become unbearable

• Methane Hydrates Tipping Point threatens to get crossed

• A Global Temperature Rise Of More than Ten Degrees Celsius By 2026?