Showing posts with label downplay. Show all posts
Showing posts with label downplay. Show all posts

Saturday, January 18, 2025

Why downplay the need for action?

The 2024 global average surface temperature was 1.55°C above the 1850-1900 average, according to WMO’s consolidated analysis of six datasets. 

[ click on images to enlarge ]
Differences between datasets are mainly due to the ways temperatures are measured, e.g. ERA5 measures the temperature of the air above oceans, whereas NASA and NOAA measure the surface temperature of the water, which is lower. There can also be differences in how temperatures are measured in areas with sea ice - the sea ice can be measured, or the water underneath the sea ice, or the air above the sea ice. Also, in some areas there once was sea ice that has meanwhile disappeared. Different ways of measuring things can raise the temperature record by as much as 0.2°C and even more in case of earlier years, where the margin of error is also larger. 

Importantly, the temperature rise in the above image is compared to the period 1850-1900, which is not pre-industrial. When using a genuinely pre-industrial base, the temperature anomaly may already have been above the 2°C threshold in 2015, when politicians at the Paris Agreement pledged that this threshold wouldn't be crossed.

[ from earlier post ]
“Individual years pushing past the 1.5 degree limit do not mean the long-term goal is shot", UN Secretary-General Antóno Guterres says: “It is important to emphasize that a single year of more than 1.5°C for a year does NOT mean that we have failed to meet Paris Agreement long-term temperature goals, which are measured over decades rather than an individual year", WMO Secretary-General Celeste Saulo adds. 

However, for this argument to hold, the average anomaly would need to fall to under 1.5°C from now. Should we really have to wait for another decade or two, before a confirmation is allowed to be issued that 1.5°C has been crossed. Isn't such a mandate part of downplaying how dire the situation is, an effort to delay the necessary action? Moreover, does such a mandate make sense? 
[ click on images to enlarge ]
[ for more background, also view the Extinction page ]
To illustrate this point, the above image uses NASA anomalies (blue dots) that are conservatively compared to NASA's default 1951-1980 base, with data going back to 2010. The image thus shows a 30-year review period centered around January 1, 2025. Eight imaginary years of data have been added beyond existing data, extending the trend into the future (yellow dots). The wide pink trend is based on both NASA existing data and these imaginary data, jointly covering data from 2010-2032. The narrow black trend is not based on imaginary data, it is purely based on existing data, from 2010-2024, showing the potential for such a trend to eventuate when using existing (i.e. past) data only.

In case such a trend would indeed eventuate, confirmation of the crossing of the 1.5°C threshold should NOT be delayed until all the years of a 30-year period have been entirely completed. In fact, 2°C (vs 1951-1980) would already be crossed early 2026. In the course of 2032, a 16°C rise would be reached, while the average anomaly for the period 2010-2032 would be higher than 3°C (vs 1951-1980) with still 7 years to go before the 30-year period would be completed.

Warnings about the potential for such a rise have been sounded before, e.g. see the extinction page.

See also the image below with daily data.
[ temperature anomaly with ENSO shading, trends added, from an earlier post ]
Human extinction at 3°C

If the temperature does indeed keep rising rapidly, the anomaly compared to pre-industrial may soon or already be higher than 3°C, implying that humans are already functionally extinct, especially if no decisive, comprehensive and effective action is taken.

Analysis by Shona and Bradshaw found that, due to co-extinction, global biodiversity collapse occurs at around 5°C heating, as discussed in a 2019 post with the warning that a rise of more than 5°C could happen within a decade, possibly by 2026, and that humans who depend on many other species will likely go extinct with a 3°C rise.


A recent study by Joseph Williamson et al. finds that many species that live together appear to share remarkably similar thermal limits. That is to say, individuals of different species can tolerate temperatures up to similar points. This is deeply concerning as it suggests that, as ecosystems warm due to climate change, species will disappear from an ecosystem at the same time rather than gradually, resulting in sudden biodiversity loss. It also means that ecosystems may exhibit few symptoms of heat stress before a threshold of warming is passed and catastrophic losses occur. 

Arctic sea ice

[ Arctic sea ice extent, click on images to enlarge ]
During the first few months of the year, Arctic sea ice is still growing in extent. In the above image, the red line and red marker shows 2025 sea ice extent. Dots mark Arctic sea ice extent on January 19 for the respective year and Arctic sea ice extent was at a record low for the time of year on January 19, 2025, despite La Niña conditions. 

A new El Niño may emerge in the course of 2025, while both Arctic sea ice extent and volume are at record low, while numerous self-reinforcing feedbacks are kicking in with accelerating ferocity and while further mechanisms are active that drive up temperatures such as high sunspots. Such a combination of mechanisms could cause a huge temperature rise and a Blue Ocean Event in 2025, threatening huge amounts of methane to erupt from the seafloor.


[ Arctic sea ice volume, click to enlarge ]
On Jan 18, 2025, the sea surface temperature south of Svalbard (green circle) was 5.1°C, 3.4°C higher than 1981-2011, as the above image shows. 

High ocean temperatures result in low Arctic sea ice volume, as illustrated by the image on the right and discussed in this earlier post.

Guy McPherson discussed the consequences of an ice-free Arctic Ocean in the video below, adding that "a near-term, ice-free Arctic Ocean—the so-called Blue Ocean Event—is the extinction-causing event over which we have the least control. The rate of environmental change in the wake of such an event will suffice to cause the extinction of all life on Earth. 
I’m not a fan." 


Climate Emergency Declaration

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.



Links

• WMO confirms 2024 as warmest year on record at about 1.55°C above pre-industrial level
https://wmo.int/news/media-centre/wmo-confirms-2024-warmest-year-record-about-155degc-above-pre-industrial-level

• Met Office - 2024: record-breaking watershed year for global climate 
https://www.metoffice.gov.uk/about-us/news-and-media/media-centre/weather-and-climate-news/2025/2024-record-breaking-watershed-year-for-global-climate

• Berkeley Earth - Global Temperature Report for 2024 
https://berkeleyearth.org/global-temperature-report-for-2024

• NASA - Goddard Institute Surface Temperature (GISTEMP v4) analysis 
https://data.giss.nasa.gov/gistemp

• NASA - Temperatures Rising: NASA Confirms 2024 Warmest Year on Record 

• pre-industrial

• Clustered warming tolerances and the nonlinear risks of biodiversity loss on a warming planet - by Joseph Williamson et al.

• Sunspots
https://arctic-news.blogspot.com/p/sunspots.html

• Arctic and Antarctic Data Archive System (ADS) of the National Institute of Polar Research of Japan
https://ads.nipr.ac.jp

• nullschool.net
https://earth.nullschool.net

• Double Blue Ocean Event 2025?
• Guy McPherson - consequences of an ice-free Arctic Ocean

• Danish Meteorological Institute - Arctic sea ice volume and thickness
https://ocean.dmi.dk/arctic/icethickness/thk.uk.php

• The first ice-free day in the Arctic Ocean could occur before 2030 - by Céline Heuzé et al. https://www.nature.com/articles/s41467-024-54508-3
als0o discussed on facebook at: 
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Saturday, October 26, 2024

Models downplay wrath of what they sow

Models that analyze what is driving up the temperature all too often omit specific sources, or when included, models all too often downplay their contribution. Accordingly, policies that are promoted based on such models are all too often ineffective or even counter-productive. 

Methane is all too often referred to as 'natural gas' originating from wetlands, swamps, cows and pigs, as if calling methane 'natural' implied that human activities were not responsible for such emissions. Moreover, people with vested interests all too often suggest that such 'natural emissions' should be captured and used for heating, cooking or industrial purposes, to offset 'human emissions'. Similarly, forest fires are all too often referred to as 'wildfires', as if human activities were not responsible for them. 

The compilation of images below shows forest fires as the largest source of carbon dioxide emissions on October 26, 2024. An image of carbon monoxide is also added (bottom right), as carbon monoxide is an indicator of forest fires. Carbon monoxide is also important since it is a precursor of tropospheric ozone and carbon monoxide depletes tropospheric hydroxyl radicals, thus extending methane's lifetime. 


The methane image (top right) shows a high presence of methane in northern Europe. The cause for this is the high temperatures anomaly in northern Europe on October 26, 2024, resulting in strong decomposition of vegetation, which comes with high emissions of carbon dioxide, carbon monoxide and methane. 


The high temperatures anomaly in northern Europe is illustrated by the above image. The image also illustrates polar amplification of the temperature rise, one of the mechanisms that drives up the temperature rise. Numerous mechanisms driving up the temperature rise are discussed in an earlier post that warns about a Double Blue Ocean Event. Thawing permafrost can cause huge emissions of carbon dioxide (CO₂), methane and nitrous oxide. 

[ from earlier post ]
Rising emissions could originate from many sources, the more so as more sinks turn into sources.
[ from earlier post ]
Many models go back only to 1750, many even use an earlier base, as if concentrations of greenhouse gases only started to rise then. 

The image on the right shows IPCC and WMO values for the rise of methane (CH₄), carbon dioxide (CO₂) and nitrous oxide (N₂O) from 1750. The image shows that: 
- Methane rose to 265% its 1750 value. - Carbon dioxide rose to 151% its 1750 value.
- Nitrous oxide rose to 125% its 1750 value.

Note that values for methane as low as 550 ppb and carbon dioxide as low as 260 ppm have been found in ice cores corresponding with periods thousands of years ago, as illustrated by the image below, from the pre-industrial page, based on Ruddiman et al. (2015). 


According to the Met Office, climate sensitivity is typically defined as the global temperature rise following a doubling of CO₂ concentration in the atmosphere compared to pre-industrial levels. Pre-industrial CO₂ was about 260 parts per million (ppm), so a doubling would be at roughly 520 ppm.

A recent study found that doubling the atmospheric CO₂ levels could cause an increase in Earth’s average temperature of 7 to 14°C (13 to 25.2°F). In the video below, Guy McPherson discusses the study.


How fast could a rise to 520 ppm CO₂ unfold? Models typically put 520 ppm CO₂ far away in the future. The image below shows an analysis based on August 2009 through July 2024 data that has a trend added pointing at 520 ppm CO₂ getting crossed in 2029 and 1200 ppm CO₂ getting crossed in early 2035. In other words, the clouds tipping point could get crossed in early 2035 due to rising CO₂ alone, and because this tipping point is measured in CO₂e, this could occur well before 2035 when including the impact of feedbacks and further mechanisms.

[ from earlier post ]

Another way the danger of rising temperatures is all too often downplayed is to suggest that many feedbacks work only over very long timescales. This narrative may be convenient for politicians who rarely bother about what happens beyond the next election. However, as discussed in a recent post, there are many mechanisms that can push up the temperature rapidly, adding up to a potential rise of more than 18°C within years.

Climate Emergency Declaration

Instead of omitting them, all mechanisms driving up the temperature should be fully included in an action plan that seeks to improve the situation. Multiple policy instruments and combinations of policy instruments should be considered for implementation, preferably through local feebates. 

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.



Links

• Copernicus - Climate Pulse
https://atmosphere.climate.copernicus.eu

• Climate Reanalyzer 
https://climatereanalyzer.org

• World Meteorological Organization (WMO) - Greenhouse Gas Bulletin - No. 20 – 28 October 2024

• Double Blue Ocean Event 2025? 
https://arctic-news.blogspot.com/2024/10/double-blue-ocean-event-2025.html

• Continuous sterane and phytane δ13C record reveals a substantial pCO2 decline since the mid-Miocene - by Caitlyn R. Witkowski et al. (2024) 



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Tuesday, February 20, 2018

IPCC seeks to downplay global warming

The graph below shows global warming for a 30-year period centered on January 2018, using NASA 2003 to January 2018 LOTI anomalies from 1951-1980, adjusted by 0.59°C to cater for the rise from preindustrial to 1951-1980, and with a polynomial trend added.


From: ECMWF Nino Plumes
Above graph shows that the 1.5°C guardrail, set at the Paris Agreement, was crossed in 2016 and that a 10°C (18°F) warming could eventuate within a decade or so.

The variations in above temperature data are strongly influenced by El Niño/La Niña. We currently are in a La Niña period, during which surface temperatures are suppressed, whereas surface temperatures in 2016 were much above the trendline, due to El Niño.

The ECMWF forecast from 1 February 2018 on the right indicates that we're heading for another El Niño, i.e. surface temperatures will be rising strongly over the coming months.

The IPCC seeks to downplay the amount of global warming that has already occurred and that looks set to eventuate over the next decade or so. A leaked draft of the IPCC 'Special Report on 1.5°C above pre-industrial' (First Order Draft of SR1.5 SPM) estimates that the global mean temperature reached approximately 1°C above pre-industrial levels around 2017/2018. The IPCC appears to have arrived at this estimate using an extrapolation or near term predictions of future warming so that the level of anthropogenic warming is reported for a 30 year period centered on today.

This 1°C IPCC estimate looks quite incredible when calculating the temperature rise using NASA's data for the two most recent years for which data are available (2016/2017), which shows a warming of 0.95°C when using a baseline of 1951-1980 and a warming of 1.23°C when using a baseline of 1890-1910.


Indeed, the temperature rise differs depending on which baseline is used, and when using preindustrial as a baseline, i.e. the baseline agreed to at the Paris Agreement, indications are that temperatures have already risen by more than 1.5°C, as also discussed in an earlier post.

Furthermore, when using a 30-year period centered on January 2018, the current temperature will have to be calculated over the past 15 years and estimated for the next 15 years, i.e. up to the year 2033.

To arrive at a 1°C rise for the 30-year period, the IPCC must somehow assume that temperatures will magically fall dramatically over the next 15 years, whereas indications are that temperatures will instead rise dramatically over the next decade or so.

The image on the right shows that 10°C (18°F) warming from preindustrial could eventuate within one decade when taking into full account the warming that could result from the elements depicted in the stacked bar. Each of these warming elements is discussed in more detail at the extinction page.

The image below shows the rise from 1750 to 2030, in surface temperatures (land+ocean), rather than in anomalies.


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


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