This month rain fell on the highest peak of Greenland for the first time ever. In that icy environment, this was so unexpected, there were no gauges in place to measure it.
In my last blog post, I described the devastating floods here, in the region of Germany where I live. There can be no doubt about the key role played by climate change in bringing about the torrential rainfall that swelled tiny rivers and killed at least 170 people and devastated a well-to-do region of one of the world’s most highly developed countries.
Extreme weather has been playing havoc around the globe.
40 years of wasted time
It is hard to imagine – but it’s now 40 years since James Hansen published his landmark paper, alerting the world to the dangers of global warming:
“It is shown that the anthropogenic carbon dioxide warming should emerge from the noise level of natural climate variability by the end of the century (…) Potential effects on climate in the 21st century include the creation of drought-prone regions in North America and central Asia as part of a shifting of climatic zones, erosion of the West Antarctic ice sheet with a consequent worldwide rise in sea level, and opening of the fabled Northwest Passage.”
Now we find ourselves bang in the middle of a chaos caused by human meddling with the workings of the planet.
No doubt about it
After four decades, the IPCC, the top climate science body of the United Nations and the World Meteorological Organization, THE global authority on the state of Earth’s climate and how human activities affect it, has confirmed that there can be absolutely no doubt that our human activities have been heating up the atmosphere, land and oceans, and that this temperature increase is already disrupting our weather and life on the planet. The latest assessment draws on the work of thousands of scientists from around the world.
Between Hansen’s paper and this 6th Assessment Report (AR6) by the IPCC lie 40 years of increasing and intensive research, with the ongoing development of satellite and other monitoring technology and ever-more-sophisticated models to forecast our future. They were also four decades of increasing greenhouse gas emissions accompanied by a fierce and dirty battle for the confidence of governments and the public, fossil fuel lobbying and a campaign of absurd denial. These were 40 years of lost time, lost opportunities to right our wrongs and halt the process of climate change.
AR6 tells us Earth has already warmed almost 1.1℃ since pre-industrial times. Many changes such as sea-level rise and glacier melt are now virtually irreversible. Escape from human-caused climate change is no longer possible. It is now affecting every continent, region and ocean on Earth, and every facet of the weather.
Present-day global concentrations of atmospheric carbon dioxide (CO₂) are higher and rising faster than at any time in at least the past two million years. The speed at which atmospheric CO₂ has increased since the industrial revolution (1750) is at least ten times faster than at any other time during the last 800,000 years, and between four and five times faster than during the last 56 million years.
About 85% of CO₂ emissions are from burning fossil fuels. The remaining 15% are generated from land use change, such as deforestation and degradation.
Both methane and nitrous oxide, the second and third biggest contributors to global warming after CO₂, have also increased more quickly, influenced by the fossil fuel industry and farming.
Oceans absorb 91% of the energy from the increased atmospheric greenhouse gases. This has led to ocean warming and more marine heatwaves, particularly over the past 15 years. Marine heatwaves cause the mass death of marine life, such as from coral bleaching events. Even if the world restricts warming to 1.5-2℃ in line with the Paris Agreement, marine heatwaves will become four times more frequent by the end of the century.
Through melting ice sheets and glaciers along with the expansion of the ocean as it warms, sea level rise is accelerating: 1.3 millimetres per year during 1901-1971, 1.9mm per year during 1971-2006, and 3.7mm per year during 2006-2018.
Ocean acidification, caused by the uptake of CO₂, has occurred over all oceans and is reaching depths beyond 2,000 metres in the Southern Ocean and North Atlantic.
The IPCC says even if Earth’s climate was stabilised soon, some climate change-induced damage could not be reversed within centuries, or even millennia, including sea level rise.
Globally, glaciers have been retreating since 1950 and are projected to continue to melt for decades after the global temperature is stabilised. Meanwhile the acidification of the deep ocean will remain for thousands of years after CO₂ emissions cease.
The prospect of permafrost in Alaska, Canada, and Russia crossing a tipping point has been widely discussed. As frozen ground thaws, large amounts of carbon accumulated over thousands of years from dead plants and animals could be released as they decompose. The report projects permafrost areas will release about 66 billion tonnes of CO₂ for each additional degree of warming. These emissions are irreversible during this century under all warming scenarios, with as yet unpredictable abrupt changes unable to be ruled out.
Earth’s surface temperature will continue to increase until at least 2050 under all emissions scenarios considered in the report. The assessment shows Earth could well exceed the 1.5℃ warming limit by the early 2030s.
Net zero is not enough
If we reduce emissions sufficiently, there is only a 50% chance global temperature rise will stay around 1.5℃ (including a temporary overshoot of up to 0.1℃). To get Earth back to below 1.5℃ warming, CO₂ would need to be removed from the atmosphere using negative emissions technologies or nature-based solutions.
Global warming stays below 2℃ during this century only under scenarios where CO₂ emissions reach net-zero around or after 2050.
The report states, with high certainty, that to stabilise the climate, CO₂ emissions must reach net zero, and other greenhouse gas emissions must decline significantly. To have a 50:50 chance of halting warming at around 1.5℃, scientists estimate that we can only emit about 500 billion tonnes of CO₂.before reaching net zero emissions. At current levels of CO₂ emissions this “carbon budget” would be used up within 12 years.
2020 confirms the worst
Shortly after the publication of the IPCC report on 9 August 2021, the State of the climate 2020 report led by NOAA National Centers for Environmental Information was released, adding the last full year’s worth of observations to the picture.
Globally, the report established that 2020 – along with 2016 and 2019 was one of the three warmest years since 1850, despite the transition in the tropical Pacific to a La Niña state in August. The La Niña phase of the El Niño Southern Oscillation (ENSO) – has a temporary cooling influence on global temperatures.
The UK Met Office’s Dr Robert Dunn is the lead editor for the global climate chapter of the report. He said: “This report adds to all the other evidence that human-induced climate change is affecting every part of the globe, but not all regions are experiencing the change at the same rate. The Arctic is continuing to warm at a faster pace than lower latitudes, but Europe’s annual average temperature is also increasing quite rapidly, with the five highest annual temperatures all occurring from 2014.”
Anomalies the new normal
Dr Kate Willett, is a co-editor for the report’s global climate chapter and author of the surface humidity section. She said: “Year-on-year the wealth of evidence of sustained climate change with long-term trends and record or near-record values across our climate system is growing and it is becoming abundantly clear that these historically unusual values of water vapour, relative humidity, evaporation, soil moisture, drought, extreme precipitation and extreme temperature, to name a few, are our new normal.
2020 saw the three main greenhouse gases reach record values. The global average for the atmospheric concentration of carbon dioxide was 412.5 parts per million (ppm). The 2020 increase in the atmospheric concentration of methane (14.8 parts per billion) was the highest such increase since systematic measurements began in the 1980s.
2020 saw the world’s highest recorded temperature since 1931, in Death Valley, in the south-western United States, at 54.4 °C. This was reached again in July 2021. We had the highest temperature recorded on the Antarctic continent, 18.3 °C. The scientists confirmed widespread marine heatwaves, mountain glaciers losing mass for the 33rd year in succession, ice loss, droughts, and wildfires.
Climate crisis requires drastic measures
A group of world-renowned climate scientists, the Climate Crisis Advisory Group, has published its assessment of the AR6 report. In light of the fact that change is happening more rapidly than predicted, the group of 15 leading climate scientists from across the world, chaired by the UK’s former chief scientific advisor Sir David King, and including Johan Rockström, director of the Potsdam Institute for Climate Impact Research in Germany, argues that ambitions for reaching net-zero emissions by 2050 will no longer be enough to avoid the worst impacts of global heating.
“It is now inevitable that the world will pass 1.5°C of warming, and that every fraction of a degree of additional warming will amplify the climate risks humanity will face”, the group writes in its paper entitled “The Final Warning Bell”. They say the Arctic Circle is arguably already beyond its tipping point.
The coming 9 years up to 2030 are decisive, says CCAG – and the chances of success are “uncomfortably low”.
So what do we have to do?
“Everyone must phase out fossil fuels at record speed (cutting emissions in half each decade); everyone must phase out methane, nitrous oxide and ozone-depleting substances at this same dizzying pace; food systems must be transformed from carbon sources to carbon sinks; and all nations must invest in keeping the carbon sinks and stocks in nature intact on land and in the oceans”, the group writes.
Why am I not feeling too optimistic about that?
Too little too late
The main message of the analysis is not encouraging:
“While emissions reduction is an essential part of the fight against climate change, it will not be enough to prevent continuing sea level rise, thawing permafrost with the release of methane, and other climate-related changes. Following a pathway leading only to net zero by 2050 is now too little too late”.
It seems to me we have all been failing to take note of an essential piece of small print in all the climate documents to date. Greenhouse gas removal is implicit in all future pathways modelled by the IPCC that meet the goals of the Paris Agreement, the paper states. “We must now also rapidly start removing greenhouse gases from the atmosphere at scale and start repairing our critically damaged climate systems”, says CCAG. The trouble is that almost all pathways assume that as yet unproven technologies will remove more CO2 from the atmosphere than is emitted.
The Climate Crisis Advisory Group pins its hopes on both nature-based solutions and man-made ‘negative emissions’ technologies to achieve a net-negative emission world. Unfortunately, it says both options have suffered from a lack of investment, policy support and in-depth research.
Clearly the cost of carbon removal systems is a key issue. Technology to capture carbon emitted in industrial processes and store it safely in the ground or under the sea, is already being used, but only on a small scale. The same applies to technologies to actively suck CO2 out of the atmosphere.
The group argues that “only technologies capable of capturing and sequestering at least one billion tons per year of CO2 each should be under consideration, since scalability is critical in any response to the current crisis”.
In planning negative emissions moves, the scientists also stress the critical importance of ensuring that projects are delivered in a ‘just’ manner that protects and empowers the most marginalised groups, including Indigenous communities. That speaks, in the first instance, for nature-based solutions. Restoring ecosystems as carbon sinks are one essential element. These methods could also bring significant biodiversity benefits. The group mentions marine-based methods such as extending the scale of marine kelp, sea grasses and seaweed farms. They also cite ocean iron fertilisation programmes, which, they say, can “generate plankton-rich forests, accompanied by burgeoning fish stocks and a huge variety of marine wildlife including whales”. Forest protection, including fire management policies are also considered essential.
No “either… or”
“If all feasible greenhouse gas removal technologies are deployed at scale, there is a reasonable chance of sequestering 30 – 40 billion tons of CO2 annually – less than the total amount being emitted currently each year,” the report states. “Greenhouse gas removal at scale is essential for stabilising the planet and its weather systems, but not sufficient – hence reinforcing the need for deep and rapid emissions reductions, and climate repair”.
By that, the group envisages dramatic actions such as refreezing the Earth’s poles and glaciers, slowing future ice melt and stabilising sea levels. Several routes for refreezing are being developed. One involves the manipulation of sea ice to increase the overall rate of growth during the early winter. Two different approaches have yet to be subjected to in-depth research: the breaking up of newly formed sea ice in the winter in order to increase the thickness of some areas whilst consequently exposing more sea water to cold air which could increase the overall rate of formation of ice whilst also providing zones of thicker ice which could potentially remain frozen over a complete summer; the spraying of sea-water onto the top of ice, thereby causing more ice to form.
The report acknowledges that research into how these actions could be carried out is in its relative infancy. I have been sceptical of these kinds of interference in natural processes – but giving the urgency dictated by the IPCC report and all the other data emerging, it seems we may not be able to rule them out. Either way – time is not on our side.
CCAG promises another report soon with more information and analysis about the methods it thinks could be deployed to repair the climate. I await it with a desperate kind of eagerness. There are those who have always argued that geo-engineering options would only serve as an excuse for the fossil fuel industry to carry on regardless. But it seems it is no longer a matter of “either… or”. Once, people argued that adaptation to climate change would distract from the need to mitigate.
“There is no contingency plan to address the resulting uncontrollable climate change; an event that would unquestionably have catastrophic impacts on civilization as we know it,”says CGAG.
When the world’s leaders and climate negotiators meet in Glasgow in November, they have an immesurable responsibility for the future of humanity and the planet that sustains us.
Sir David King puts it in a nutshell: “there really is no room left for manoeuvre; this is our ‘now or never’ moment,” he says.
He and his colleagues are calling on nations not only to pledge and implement the necessary emissions reductions, but also to provide funding for research and deployment of technologies to remove emissions or repair the climate.
“The latest IPCC AR6 report is the surest assessment to date of the global catastrophe on our hands should our leaders not take immediate, concerted action in confronting the climate crisis.”
What more can I say?