By Erika Clugston, The Beam with further specification by M. Venner to clarify 1.5 C part of the estimates, after going to the source at Mercator. See David Spratt’s summary of the literature, further down.
The Carbon Budget is an estimation of how much carbon can be released into the atmosphere before we reap the consequences of catastrophic climate changes. You can check in regularly with this Carbon Countdown Clock, which currently estimates we’ll hit the 1.5 C target we need to try to stay below, in just one month and 21 days. That’s for the medium estimate. We’re 2 yrs past or have 2 years remaining if you take the higher or lower.
According to the Global Carbon Budget 2017, in order to avoid 2°C of warming, “global CO2 emissions need to decline rapidly and cross zero emissions around 2050.” In other words, not only must emissions come to zero, but must go into negative carbon emissions. Going below zero means that we are removing more carbon from the atmosphere than we are putting into it. It would be better (and more honest calculating) to cut emissions much faster/sooner and not rely on technology that does not yet exist and that looks highly unaffordable and further displaces the natural environment. Currently planning is too much based on such negative-emissions scenarios, according to a 2018 scientific study in Scientific Reports,
A worldwide temperature increase of 2°C would have devastating impacts on the Earth, causing rising oceans, increasing forest fires, intense droughts, and other negative environmental impacts. The goals of the Paris Agreement are to keep the global temperature below 2°C for the long term future, however many are saying it’s not enough and won’t prevent severe warming.
As of June 2018, Schroders predicts a temperature rise based on levels of global commitment and progress of at least 4.0°C by 2100. At this temperature, this will lead to a $700 billion rise in annual climate investment, negative impact on global companies, with a baseline longterm negative impact on GDP. The Climate Action Tracker predicts that the global temperature is likely to surpass 4.0°C by 2100, and could in fact be closer to 4.8 °C, while recent scientific forecasts suggest that in the next five years we’ll likely reach reach 1.5 °C above pre-industrial levels.
We’re already beginning to see rising global temperatures. According to NASA and NOAA, May 2018 was the fourth warmest May on record and temperatures keep rising. 2017 was the hottest year on record, with extreme weather recorded across the globe. We can only expect more of the same.
Oil and gas are major contributors to greenhouse gas emissions. As of June 2018, oil and gas investments are factoring to create a temperature scenario of 4.3 °C as estimated by Schroders. This amount of investments is not aligned to the Paris Agreement and has to decline sharply.
Apart from many reports that have been exceedingly inaccurate (like the IPCC, IEA, also mentioned) the Bloomberg New Energy Finance Reports have made the best predictions and believes in 50% solar and wind by 2050 .
According to the IPCC Fifth Assessment Report, Climate Change 2014: Mitigation of Climate Change, using baseline scenarios “direct CO2 emissions from the energy supply sector are projected to almost double or even triple by 2050 [..] unless energy intensity improvements can be significantly accelerated beyond the historical development.”
According to a more recent report by IEA, World Energy Outlook 2017, global energy demand will grow 30% by 2040 and with a third of energy demand growth coming out of India. Oil demands will continue to grow, increasing to 105 million barrels a day. However, there is a growth of clean energy, with solar becoming the most affordable form of new electricity in many countries.
The World Economic Forum prepared various ‘alternative futures’ for the oil and gas industry, which you can peruse here, but the main takeaway is that “the need for oil and gas to fuel global economic well-being for an expanding middle-class population in the developing world will increase oil and gas demand significantly over the next three decades, in spite of significant improvements in energy efficiency.” This is backed up by others, such as BP and the IEA, whose predictions contend that the world’s oil consumption will not peak until the late 2030s, despite the rise of electric vehicles and clean energy. Another prediction made in the International Energy Agency report is that the United States will come to dominate crude and gas production by 2040, due to major growth in shale oil. However they suggest that US shale oil will peak in the 2020s at 17 million bpd. Again, important to mention that especially the IPPC, IEA and Oil&Gas company reports (like those by BP) have been heavily criticized and often have a vested interest in certain statements.
Ice Shield Loss & Sea Level Rise
According to a recently published study by IMBIE, coastal cities need to be on high alert and expect to face dangerously high sea-levels in less than a decade. NASA scientists are calling this study “the most robust study of the ice mass balance of Antarctica to date.” Since 1901, ice losses and melting glaciers caused a sea-level rise at an average rate of 1.7 mm/yr. However, from 1992 to the present, the ice sheet has lost almost 3 trillion tons of ice, creating a sea-level rise of 8mm/yr. 40% of that has been in only the last five years. A recent study explains that as warm ocean waters carve out crevasses underneath the ice shelves, they crack, thin out, and break off in pieces into the ocean, causing it to rise. If rising temperatures & greenhouse gasses continue at current rates, here’s what to expect:
- The sea-level rise could be more than 1cm per year.
- If polar ice-sheet loss doubles every ten years, the sea-level could rise one meter in 50 years.
- By 2100, 70% of coastlines will experience the effects of rising sea-levels.
- Periods of occasional stability will occur amidst rapid glacial retreat.
According to a recent study by researchers from Radboud University, the University of Cambridge (C-EENRG), Cambridge Econometrics, The Open University (UK) and the University of Macau and published in Nature Climate Change, there is a sizeable Carbon Bubble.
“The study findings support the existence of a carbon bubble which, if not deflated early, could lead to a discounted global wealth loss of between 1 to 4 trillion dollars, a loss comparable to what triggered the 2007 financial crisis.”
We’re going to update this article in a few months with recent reports and studies. Please leave us comments with interesting reports we may not have mentioned.
1.5°C of warming is closer than we imagine, just a decade away
Global warming of 1.5°C is imminent, likely in just a decade from now. That’s the stunning conclusion to be drawn from a number of recent studies, surveyed below.
So how does hitting warming of 1.5°C a decade from now square with the 2015 Paris Agreement’s goal of “holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C”? In two words, it doesn’t.
The Paris text was a political fix in which grand words masked inadequate deeds. The voluntary national emission reduction commitments since Paris now put the world on a path of 3.4°C of warming by 2100 (as illustrated), and more than 5°C if high-end risks including carbon-cycle feedbacks are taken into account.
The Paris outcome is an emissions path continuing to rise for another fifteen years, even though it is clear that “if the 1.5°C limit should not be breached in any given year, the budget (is) already overspent today”. Two years ago, Prof. Michael E. Mann noted: “And what about 1.5°C stabilisation? We’re already overdrawn.”
In fact, the emission scenarios associated with the Paris goal show that warming will “overshoot” the 1.5°C target by up to half a degree, before cooling back to it by the end of this century. Those scenarios rely unduly on unproven Bio-Energy with Carbon Capture and Storage (BECCS) technology in the second half of the century, because the Paris Agreement does not encompass the steep emissions reductions that are required right now.
Average global warming is now 1.1°C above the late nineteenth century, and the rate of warming is likely to accelerate due to record levels of greenhouse gas emissions, a higher climate sensitivity and because efforts to clean up some of the world’s dirtiest power plants is reducing the emission of aerosols(mainly sulphates) which have a very short-term cooling impact.
So now, in 2018, the benchmark of 1.5°C of warming is just a decade away or even less, according to multiple lines of evidence from climate researchers:
HENLEY and KING: In 2017, Melbourne researchers Ben Henley and Andrew King published Trajectories toward the 1.5°C Paris target: Modulation by the Interdecadal Pacific Oscillation on the impact of the Interdecadal Pacific Oscillation (IPO) on future warming. The IPO is characterized by sea surface temperature fluctuations and sea level pressure changes in the north and south Pacific Ocean that occur on a 15-30 year cycle. In the IPO’s positive phase, surface temperatures are warmer due to the transfer of ocean heat to the atmosphere. The IPO has been in a negative phase since 1999 but recent predictions suggest that it is now moving to a positive phase. The authors found that “in the absence of external cooling influences, such as volcanic eruptions, the midpoint of the spread of temperature projections exceeds the 1.5°C target before 2029, based on temperatures relative to 1850–1900”. In more detail,”a transition to the positive phase of the IPO would lead to a projected exceedance of the target centered around 2026”, and “if the Pacific Ocean remains in its negative decadal phase, the target will be reached around 5 years later, in 2031”.
|Projected temperature rises with IPO in positive mode (red) and negative mode (blue) (Henley and King, 2017)|
JACOB et al: A set of four future emission scenarios, known as Representative Concentration Pathways (RCPs) have been used since 2013 as a guide for climate research and modelling. The four pathways, known as RCPs 2.6, 4.5, 6 and 8.5, are based on the total energy imbalance in the energy system by 2100. RCP8.5 is the highest, and is the current emissions path. In Climate Impacts in Europe Under +1.5°C Global Warming, released this year, Daniela Jacob and her co-researchers found that the world is likely to pass the +1.5°C threshold around 2026 for RCP8.5, and “for the intermediate RCP4.5 pathway the central estimates lie in the relatively narrow window around 2030. In all likelihood, this means that a +1.5°C world is imminent.”
KONG AND WANG: In a study of projected permafrost change, Responses and changes in the permafrost and snow water equivalent in the Northern Hemisphere under a scenario of 1.5 °C warming, researchers Ying Kong and Cheng-Hai Wang use a multi-model ensemble mean from 17 global climate models, with results showing that the threshold of 1.5°C warming will be reached in 2027, 2026, and 2023 under RCP2.6, RCP4.5, RCP8.5, respectively. On the present, high-emissions RCP8.5 path, the estimated permafrost area will be reduced by 25.55% or 4.15 million square kilometres at 1.5°C of warming.
XU and RAMANATHAN: A recent study by Yangyang Xu and Veerabhadran Ramanathan, Well below 2 °C: Mitigation strategies for avoiding dangerous to catastrophic climate changes, looked at the high-end or “fat-tail” risks of climate change, in an analysis of the existential risks in a warming world. One of two baseline scenarios used, named Baseline-Fast, assumed an 80% reduction in fossil fuel energy intensity by 2100 compared to 2010 energy intensity. In this scenario, the level of atmospheric carbon dioxide had reached 437 parts per million (ppm) by 2030 and the warming was 1.6°C, suggesting that the 1.5°C would be exceed around 2028. The study also found that under the Baseline-Fast scenario warming would reach 2.4°C by 2050. It is discussed in more detail here.
ROGELJ et al: In Scenarios towards limiting global mean temperature increase below 1.5°C, Joeri Rogelj and co-researchers plot future emissions and warming based on five distinct “Shared Socioeconomic Pathways” (SSPs). These “present five possible future worlds that differ in their population, economic growth, energy demand, equality and other factors”, according to CarbonBrief. The fourth and fifth paths are the world we now live in: SSP4 is a world of “high inequality”, whilst SSP5 is a world of “rapid economic growth” and “energy intensive lifestyles”. If we look at these paths charted against projected temperatures, then SSP5 exceeds 1.5°C in 2029 and SSP4 by 2031.
|Projected global mean temperature for five Shared Socioeconomic Pathways (CarbonBrief)|
SCHURER et al: In Interpretations of the Paris climate target, Andrew Schurer and colleagues demonstrate that the IPCC uses a definition of global mean surface temperature which underestimates the amount of warming over the pre-industrial level. The underestimation is around 0.3°C, and a higher figure includes the effect of calculating warming for total global coverage rather than for the coverage for which observations are available, and warming from a true pre-industrial, instead of a late-nineteenth century, baseline. If their finding were applied, warming would now be 1.3°C or more, and hitting the 1.5°C benchmark would be just half a decade away.
CONSEQUENCES: In their 2017 paper on catastrophic climate risks, Xu and Ramanathan defined 1.5°C as a benchmark for “dangerous” climate change, compared to the convention policy-making mark of 2°C. But even this lower mark may be too optimistic, given the impacts we have seen at both poles in the last decade. In any case, in contemplating the imminent reality of the 1.5°C benchmark, it is important to consider what is at stake:
- In another decade and by 1.5°C, we may well have witnessed an Arctic free of summer sea ice, a circumstance that just two decades ago was not expected to occur for another hundred years. The consequences would be devastating.
- In 2012, then NASA climate science chief James Hansen told Bloomberg that: “Our greatest concern is that loss of Arctic sea ice creates a grave threat of passing two other tipping points – the potential instability of the Greenland ice sheet and methane hydrates… These latter two tipping points would have consequences that are practically irreversible on time scales of relevance to humanity.” One highly-regarded research paper in 2012 estimated that “the warming threshold leading to a monostable, essentially ice-free state is in the range of 0.8–3.2°C, with a best estimate of 1.6°C” for the Greenland ice sheet.
- In 2015, researchers looked at the damage to system elements — including water security, staple crops land, coral reefs, vegetation and UNESCO World Heritage sites — as the temperature increases. They found all the damage from climate change to vulnerable categories like coral reefs, freshwater availability and plant life could happen before 2°C warming is reached, and much of it before 1.5°C warming.
- In 2009, Australian scientists contributed to an important research paper which found that preserving more than 10% of coral reefs worldwide would require limiting warming to below 1.5°C. Recent research found that the surge in ocean warming around the Great Barrier Reef in 2016, which led to the loss of half the reef, has a 31% probability of occurring in any year at just the current level of warming. In other words, severe bleaching and coral loss is likely on average every 3–4 years, whereas corals take 10–15 years to recover from such events.
- There is evidence that a 1.5º C global rise in temperature is likely to cause widespread thawing of continuous permafrost as far north as 60°N. At 1.5°C, the loss of permafrost area is estimated to be four million square kilometres.
- At 1.5°C, it is very likely that conclusions first aired in 2014 –– that sections of the West Antarctic Ice Sheet have already passed their tipping points for a multi-meter sea-level rise –– will have been confirmed. Four years ago scientists found that “the retreat of ice in the Amundsen Sea sector of West Antarctica was unstoppable, with major consequences – it will mean that sea levels will rise 3 feet worldwide… Its disappearance will likely trigger the collapse of the rest of the West Antarctic ice sheet, which comes with a sea-level rise of between 15-25 feet. Such an event will displace millions of people worldwide.” Leading cryosphere researcher Eric Rignot muses: “You look at West Antarctica and you think: How come it’s still there?”
- By 1.5°C, a sea-level rise of many meters, and perhaps tens of meters (60 feet or more) will have been locked into the system in the longer term. In past climates, carbon dioxide levels of around 400 ppm (which we exceeded three years ago) have been associated with sea levels around 75 feet above the present. And six years ago, Prof. Kenneth G. Miller noted that “the natural state of the Earth with present carbon dioxide levels is one with sea levels about 20 meters (60 feet) higher than at present”. The expected sea-level rise this century is generally in the range of one to two metres, but higher increases cannot be ruled out. The US military, for example, use one- and two-meter sea-level-rise scenarios in their planning.
Clearly, as Former NASA climate chief James Hansen and co-authors wrote last year, “the world has overshot the appropriate target for global temperature”. They noted a danger of 1.5°C and 2°C targets is that they are far above the Holocene (human civilisation) temperature range, and if such temperature levels are allowed to long exist they will spur “slow” amplifying feedbacks which have potential to run out of humanity’s control. Hence “limiting the period and magnitude of temperature excursion above the Holocene range is crucial to avoid strong stimulation of slow feedbacks”.
And in all this evidence, what worries me most? It is my experience that with few exceptions neither climate policy-makers nor climate action advocates have a reasonable understanding of the imminence of 1.5°C and its consequences.