Emissions reduction efforts in the next decade pledged by governments under the Paris climate agreement are by far not sufficient to attain the explicit aim of the agreement — they will not keep warming below the 2-degrees-limit.
Emissions in 2030 would need to be at least 20 percent below what countries have pledged under the Paris climate agreement to keep costs and CO2 removal in check.
Rapid short-term emissions reductions are the most robust way of preventing climate damages and large-scale deployment of carbon removal technologies can only be avoided when reliable CO2 prices are introduced as soon as possible.
Rapid greenhouse-gas emissions reductions are needed if governments want to keep in check both the costs of the transition towards climate stabilization and the amount of removing already emitted CO2 from the atmosphere. To this end, emissions in 2030 would need to be at least 20 percent below what countries have pledged under the Paris climate agreement, a new study finds….
Removing CO2 from the atmosphere through technical methods including carbon capture and underground storage (CCS) or increased use of plants to suck up CO2 comes with a number of risks and uncertainties, and hence the interest of limiting them.
….”Emissions reduction efforts in the next decade pledged by governments under the Paris climate agreement are by far not sufficient to attain the explicit aim of the agreement — they will not keep warming below the 2-degrees-limit,”…”To stabilize the climate before warming crosses the Paris threshold, we either have to undertake the huge effort of halving emissions until 2030 and achieving emission neutrality by 2050 — or the emissions reductions would have to be complemented by CO2 removal technologies. In our study, we for the first time try to identify the minimum CO2 removal requirements — and how these requirements can be reduced with increased short-term climate action.”
…It turns out that, according to the computer simulations done by the scientists, challenges for likely keeping warming below the threshold agreed in Paris would increase sharply if CO2 removal from the atmosphere is restricted to less than 5 billion tons of CO2 per year throughout the second half of the century. This is substantial. It would mean for instance building up an industry for carbon capture and storage that moves masses comparable to today’s global petroleum industry. Still, 5 billion tons of CO2 removal is modest compared to the tens of billion tons that some scenarios used in climate policy debates assume. Current CO2 emissions worldwide are more than 35 billion tons per year…
…first, rapid short-term emissions reductions are the most robust way of preventing climate damages, and second, large-scale deployment of CDR technologies can only be avoided when reliable CO2 prices are introduced as soon as possible….”Ramping up climate policy ambition for 2030 to reduce emissions by 20 percent is economically feasible. It is all about short-term entry points: rapidly phasing out coal in developed countries such as Germany and introducing minimum prices for CO2 in pioneer coalitions in Europe and China makes sense almost irrespective of the climate target you aim for. In contrast, our research shows that delaying action makes costs and risks skyrocket. People as well as businesses want stability, and this is what policy-makers can provide — if they act rapidly.”
Jessica Strefler, Nico Bauer, Elmar Kriegler, Alexander Popp, Anastasis Giannousakis, Ottmar Edenhofer. Between Scylla and Charybdis: Delayed mitigation narrows the passage between large-scale CDR and high costs. Environmental Research Letters, 2018; 13 (4): 044015 DOI: 10.1088/1748-9326/aab2ba
Climate-smart agriculture (CSA) has the potential to help farmers implement both adaptation and mitigation practices. The mitigation aspect of CSA is often not considered by farmers due to a high discount rate and, as such, adaptation is usually the priority concern…
…Approaches such as climate-smart agriculture (CSA)  are intended to help to reorient agricultural systems to support food security under conditions of climate change and increased climate variability. Successful CSA consists of simultaneously achieving three goals or pillars according to FAO : (i) sustainably increasing agricultural productivity to support equitable increases in incomes, food security and development; (ii) adapting and building resilience to climate change from the farm to national levels; and (iii) reducing or removing greenhouse gas (GHG) emissions where possible…
…In agricultural research, scaling out is the objective to reach a wide number of farmers with improved practices , and scaling up occurs when institutional buy-in and policies are influenced at higher levels . Though there are a wide array of challenges to scaling CSA, many of these can be addressed through technical, social, economic, and policy innovations . Many of these are social processes and, though much of the work on adaptation has built on the ideas of capabilities associated with the “five capitals” (financial, natural, human, physical and social), we have perhaps lost sight of many of the complexities and nuances associated with social capital in particular ….
….In order to achieve a 1.5°C scenario, consideration of the characteristics of local networks should figure into the design of any community engagement effort [26••; 51 ; 52]. This is especially the case now that the call for “mainstreaming” synergistic adaptation-mitigation practices into development policy has become part of the standard refrain [24 ; 53]. With an understanding of how adaptation strategies synergize across scale as a function of the existing networks, a goal should be to leverage community strengths and design strategies that maximize mitigation as a direct co-benefit of the implementation of adaptation practices. This is even more important where “…motivation to pursue long-term, broad-based plans, and/or to respond to community priorities, may be constrained” [54••] (p.17). An examination of local networks thus has the potential to serve as something of a first pass for establishing both the relevance and transferability of different CSA practices at different scales, while simultaneously serving as basis for designing the corresponding institutional arrangements that will better facilitate the uptake of practices with mitigation co-benefits depending on local socio-ecological circumstances [49•]…
…We argue that achieving a 1.5°C scenario requires small-scale farmers’ contributions through the implementation of strategies that provide mitigation co-benefits and synergies linked to adaptation but that additional understanding of farmers network context is a critical first step. A 1.5°C future could consist of small-scale farmers increasing their resilience through low carbon adaptation to climate change, contributing to the global mitigation efforts. However, this will require CSA options to be implemented widely and rapidly, meaning uptake by most of the small-scale farmers as soon as possible. Explicit acknowledgement of how social capital and networks operate in relation to climate challenges thus has the potential to be a critical ingredient when designing and implementing CSA at scale.
Social networks are likely a key to facilitate scaling up and out processes by enabling individuals and institutions to interact across scales, guiding their decision making processes [34••], and building social capital that spreads CSA strategies….
Deissy Martinez-Baron, Guillermo Orjuela, Giampiero Renzoni, Ana María Loboguerrero Rodríguez, Steven D Prager.
Up to half of plant and animal species in the world’s most naturally rich areas, such as the Amazon and the Galapagos, could face local extinction by the turn of the century due to climate change if carbon emissions continue to rise unchecked. Even if the Paris Climate Agreement 2°C target is met, these places could lose 25% of their species according to a landmark new study by the University of East Anglia, the James Cook University, and WWF.
Published today in the journal Climatic Change and just ahead of Earth Hour, the world’s largest environmental event, researchers examined the impact of climate change on nearly 80,000 plant and animal species in 35 of the world’s most diverse and naturally wildlife-rich areas….
….If there was a 4.5°C global mean temperature rise, the climates in these areas are projected to become unsuitable for many the plants and animals that currently live there meaning:
Up to 90% of amphibians, 86% of birds and 80% of mammals could potentially become locally extinct in the Miombo Woodlands, Southern Africa
The Amazon could lose 69% of its plant species
In south-west Australia 89% of amphibians could become locally extinct
60% of all species are at risk of localised extinction in Madagascar
The Fynbos in the Western Cape Region of South Africa, which is experiencing a drought that has led to water shortages in Cape Town, could face localised extinctions of a third of its species, many of which are unique to that region…..
….Dr Jeff Price, coordinator of the Wallace Initiative and also from UEA, said: “This research provides a view on the differing spatial impacts of climate change on biodiversity. It shows the benefits of combining citizen science with the research and resources of highly-ranked Universities to assist an NGO with their conservation activities.”
R. Warren, J. Price, J. VanDerWal, S. Cornelius, H. Sohl. The implications of the United Nations Paris Agreement on climate change for globally significant biodiversity areas. Climatic Change, 2018; DOI: 10.1007/s10584-018-2158-6
Plantations would have to be massive in scale, and their value is still unproven.
Relying on BECCS-bioenergy with carbon capture and storage- via the land system is a very high risk to the Earth system in general.
The Intergovernmental Panel on Climate Change, in its Fifth Assessment Report, presented more than 100 modeled scenarios that it said had a high likelihood of keeping global temperatures within 2 degrees Celsius of preindustrial levels. Nearly all of them assumed that negative emissions technology would be viable and widely used, particularly BECCS.
….a much bigger geoengineering strategy that some experts hope could reduce global emissions by removing carbon dioxide from the atmosphere [is] known as “negative emissions”…
The idea calls for massive plantations of trees and other crops to draw carbon dioxide out of the air. The trees could then be harvested for the production of energy or biofuels, with carbon capture technology used to sequester their emissions. The whole process would be carbon-negative. This could theoretically cool the climate. But it would have to be done at a massive scale.
It’s still almost an entirely hypothetical concept. But it has rapidly risen to prominence as a strategy for meeting the world’s climate targets established under the Paris Agreement. It’s called “bioenergy with carbon capture and storage,” or BECCS….
…A study published in the journal Nature Climate Change in January is among the latest to raise doubts. It suggests that the large-scale deployment of BECCS—which calls for massive, managed plantations of trees—would likely require an unsustainable use of land, water and other resources.
“Our main message is that really relying on BECCS via the land system is a very high risk to the Earth system in general,” said the paper’s lead author, Vera Heck of the Potsdam Institute for Climate Impact Research in Germany.
The research relies on the idea of “planetary boundaries,” a concept first developed by scientists in 2009. It describes nine environmental thresholds, from freshwater use and land changes to ocean acidification. Pushing any of these boundaries too far, the framework suggests, could result in irreversible consequences for Earth systems. Climate change itself is listed as one of the planetary boundaries….
…Just this month, the European Academies Science Advisory Council released a report warning against unrealistic assumptions about carbon dioxide removal, or CDR.
…A recent study in the Proceedings of the National Academy of Sciences points out that nations need to have the resources to transport harvested biomass to processing facilities if they’re going to use it for energy. And once it’s been burned, these nations must also have access to locations suitable for storing the captured carbon dioxide underground.
…As experts call for greater caution in the assumptions being made about future technology, modelers may explore more scenarios in which negative emissions are less aggressively deployed….
Even if we stay under 2C, extreme events -heat, floods, drought – will become more likely in the decades ahead. And if countries do not meet the Paris climate agreement goals, the risks will be even greater
Overall, up to 60% of locations across North America, Europe, East Asia and parts of southern South America would likely see at least a 3x and up to 5x increase in some areas increase in various extreme events, according to a Stanford study published yesterday in the journal Science Advances.
The country pledges to the Paris climate accord may put the world on track to warm by about 3 C, unless significantly greater climate action is promised—and soon.
Events like record-setting heat, extreme rainfall and drought will happen more frequently around the world even if global climate targets are met, new research suggests. And missing those targets could make the risk even worse.
…the pledges world nations have submitted under the Paris Agreement are likely still not enough to keep global temperatures within the 2 C threshold envisioned by the accord. Experts suggest that the pledges may put the world on track to warm by about 3 C, unless significantly greater climate action is promised—and soon.
“In addition to not meeting the global temperature target, those commitments also imply substantial increase in the probability of record-setting events,” said Noah Diffenbaugh, a Stanford University climate researcher and the new study’s lead author. “Not only hot events but wet events, and also in other regions of the world, dry events as well.”…
….Heat records are likely to be among the most sensitive to future climate change. Record-breaking nighttime temperatures have already been increasing across 90 percent of the studied areas, the research suggests, and these records may increase by at least fivefold across half of Europe and a quarter of East Asia.Extreme wet events and milder cold spells are also expected to increase throughout the world, and extreme dry events will see an uptick in certain regions, mainly in the midlatitudes.
Strengthening the Paris pledges could help significantly reduce the risks of extreme climate events, the new research suggests, although it warns that these events will still become more frequent in the future, even if temperature increases stay under 2 C.
….The findings, overall, carry a double warning. First, even with aggressive climate action, extreme climate events are likely to increase throughout much of the world—and human societies should brace themselves for that future, no matter what. But those mitigation efforts are still sorely needed, the research also suggests. Without them, the risks could be far more intense.
Noah S. Diffenbaugh, Deepti Singh, and Justin S. Mankin. Unprecedented climate events: Historical changes, aspirational targets, and national commitments. Science Advances, 14 Feb 2018 DOI: 10.1126/sciadv.aao3354
European national science academies report warns tepid emission cuts not enough.
A new European Academies Science Advisory Council (EASAC) report looks at a number of options, including reforestation, soil management, plankton fertilization, industrial CO2 capture plants, biofuels with emissions injected underground for storage, and even the boosting of bedrock weathering reactions.
The report’s conclusions: we have to develop carbon dioxide removal schemes more aggressively, but we also have to cut our emissions enough that we don’t rely on those schemes to save us.
….Those scenarios involved a substantial deployment of technologies to actively remove CO2 from the atmosphere. Without those technologies, we’re even further from sufficient emissions cuts.
That leaves us with a crucial question: can carbon dioxide removal techniques be scaled up to the necessary level in time? A new European Academies Science Advisory Council (EASAC) report—reviewed and endorsed by the national academies of more than two dozen countries—evaluates the outlook for carbon dioxide removal. And it’s not optimistic.…
….The EASAC report finds that few options look like they could scale up to three or four billion tons. And more importantly, none is on track to do so at this point. Reforestation and accumulating carbon in agricultural soils are probably the easiest options to make progress on, for example, but we’re currently still doing the opposite of these things: deforestation and soil degradation are adding to our greenhouse gas emissions, not counteracting them….
….The EASAC report’s conclusions are basically twofold: we have to develop carbon dioxide removal schemes more aggressively, but we also have to cut our emissions enough that we don’t rely on those schemes to save us….
Slashing emissions to Paris climate agreement targets could reduce impacts on CA vegetation 20-30% per new UC Davis, USGS, CDFW, NPS study
Cutting emissions so that global temperatures increase by no more than 2 degrees Celsius (3.2 degrees Fahrenheit) could reduce those impacts by half, with about a quarter of the state’s natural vegetation affected.
It projects that at current rates of greenhouse gas emissions, vegetation in southwestern California, the Central Valley and Sierra Nevada mountains becomes more than 50 percent impacted by 2100, including 68 percent of the lands surrounding Los Angeles and San Diego.
Areas projected to be more resilient include some coastal areas and parts of northwestern California.
Current levels of greenhouse gas emissions are putting nearly half of California’s natural vegetation at risk from climate stress, with transformative implications for the state’s landscape and the people and animals that depend on it, according to a study led by the University of California, Davis. However, cutting emissions so that global temperatures increase by no more than 2 degrees Celsius (3.2 degrees Fahrenheit) could reduce those impacts by half, with about a quarter of the state’s natural vegetation affected.
The study, published in the journal Ecosphere, asks: What are the implications for the state’s vegetation under a business-as-usual emissions strategy, where temperatures increase up to 4.5 degrees Celsius by 2100, compared to meeting targets outlined in the Paris climate agreement that limit warming to 2 degrees Celsius?
“At current rates of emissions, about 45-56 percent of all the natural vegetation in the state is at risk, or from 61,190 to 75,866 square miles,” said lead author James Thorne, a research scientist with the Department of Environmental Science and Policy at UC Davis. “If we reduce the rate to Paris accord targets, those numbers are lowered to between 21 and 28 percent of the lands at climatic risk.”…
…“This is the map of where we live,” Thorne said. “The natural landscapes that make up California provide the water, clean air and other natural benefits for all the people who live here. They provide the sanctuary for California’s high biodiversity that is globally ranked. This map portrays the level of climate risk to all of those things. In some cases, the transformation may be quite dramatic and visible, as is the case with wildfire and beetle outbreaks. In other cases, it might not be dramatically visible but will have impacts, nevertheless.”…
…the data is helping the agency understand not only which parts of the state are vulnerable to climate change, but also which areas are more resilient, such as some coastal areas and parts of northwestern California, so they can ensure they remain resilient….
Decades of diplomatic efforts to stem global warming have proven ineffectual because too many strategies have been taken off the table.
But what definitely won’t suffice is a climate strategy built out of wishful thinking: the proposition that countries can be cajoled and prodded into increasing their ambition to cut emissions further, and that laggards can be named and shamed into falling into line.
There is no momentum for investing in carbon capture and storage, since it could be seen as condoning the continued use of fossil fuels. Nuclear energy, the only source of low-carbon power ever deployed at the needed scale, is also anathema. Geoengineering, like pumping aerosols into the atmosphere to reflect the sun’s heat back into space, is another taboo. But eventually, these options will most likely be on the table, as the consequences of climate change come more sharply into focus…
Global emissions of greenhouse gases amounted to the equivalent of some 30 billion tons of carbon dioxide a year — excluding those from deforestation and land use. Worried about its accumulation, the gathered scientists and policymakers called on the world to cut CO2 emissions by a fifth.
That didn’t happen, of course. By 1997, when climate diplomats from the world’s leading nations gathered to negotiate a round of emissions cuts in Kyoto, Japan, emissions had risen to some 35 billion tons and the global surface temperature was roughly 0.7 degrees Celsius above the average of the late 19th century.
It took almost two decades for the next breakthrough. When diplomats from virtually every country gathered in Paris just over two years ago to hash out another agreement to combat climate change, the world’s surface temperature was already about 1.1 degrees Celsius above its average at the end of the 1800s. And greenhouse gas emissions totaled just under 50 billion tons….
…Climate diplomats in Paris didn’t merely reassert prior commitments to keep the world’s temperature less than 2 degrees above that of the “preindustrial” era — a somewhat fuzzy term that could be taken to mean the second half of the 19th century. Hoping to appease island nations like the Maldives, which are likely to be swallowed by a rising ocean in a few decades, they set a new “aspirational” ceiling of 1.5 degrees.
To stick to a 2 degree limit, we would have to start reducing global emissions for real within about a decade at most — and then do more. Half a century from now, we would have to figure out how to suck vast amounts of carbon out of the air. Keeping the lid at 1.5 degrees would be much harder still.
And yet, when experts tallied the offers made in Paris by all the countries in the collective effort, they concluded that greenhouse gas emissions in 2030 would exceed the level needed to remain under 2 degrees by 12 to 14 billion tons of CO2.
Are there better approaches? The “climate club” proposed by the Yale University economist William Nordhaus has the advantage of including an enforcement device, which current arrangements lack: countries in the club, committed to reducing carbon emissions, would impose a tariff on imports from nonmembers to encourage them to join.
Martin Weitzman of Harvard University supports the idea of a uniform worldwide tax on carbon emissions, which might be easier to agree on than a panoply of national emissions cuts. One clear advantage is that countries could use their tax revenues as they saw fit.
Mr. Barrett argues that the Paris agreement could be supplemented with narrower, simpler deals to curb emissions of particular gases — such as the 2016 agreement at a 170-nation meeting in Kigali, Rwanda, to reduce hydrofluorocarbon emissions — or in particular industries, like aviation or steel.
Maybe none of this would work. The climate club could blow up if nonmembers retaliated against import tariffs by imposing trade barriers of their own. Coordinating taxes around the world looks at least as difficult as addressing climate change. And Mr. Barrett’s proposal might not deliver a breakthrough on the scale necessary to move the dial.
…But what definitely won’t suffice is a climate strategy built out of wishful thinking: the proposition that countries can be cajoled and prodded into increasing their ambition to cut emissions further, and that laggards can be named and shamed into falling into line.
Inveigled by three decades of supposed diplomatic progress — coupled with falling prices of wind turbines, solar panels and batteries — the activists, technologists and policymakers driving the strategy against climate change seem to have concluded that the job can be done without unpalatable choices. And the group is closing doors that it would do best to keep open.
There is no momentum for investing in carbon capture and storage, since it could be seen as condoning the continued use of fossil fuels. Nuclear energy, the only source of low-carbon power ever deployed at the needed scale, is also anathema. Geoengineering, like pumping aerosols into the atmosphere to reflect the sun’s heat back into space, is another taboo.
But eventually, these options will most likely be on the table, as the consequences of climate change come more sharply into focus. The rosy belief that the world can reduce its carbon dependency over a few decades by relying exclusively on the power of shame, the wind and the sun will give way to a more realistic understanding of possibilities.
a broader range of scenarios is needed to support international policymakers in the target of limiting climate change to under 2°C above pre-industrial levels, and to avoid potential negative environmental and social consequences of carbon dioxide removal on a massive scale.
87% of the scenarios in the IPCC 5th Assessment Report that limit climate change to less than 2°C rely heavily on negative emissions in the second half of the century, with most of the carbon dioxide removal coming from a suite of technologies known as Bioenergy with Carbon Capture and Storage (BECCS)
massive implementation of these type of land-based carbon dioxide removal strategies would have impacts on both the environment and the food system, with previous research showing trade-offs for food security and environmental conservation.
reliance on future negative emissions to achieve climate goals may also fail to account for feedbacks in the climate system such as methane release from thawing permafrost, which are not yet fully understood
A new article lays the groundwork for alternative climate mitigation scenarios that place less reliance on unproven negative emissions technologies in the future.
…”Many currently used emissions pathways assume that we can slowly decrease fossil fuel emissions today and make up for it later with heavy implementation of negative emissions technologies,” says IIASA Ecosystems Services and Management Program Director Michael Obersteiner, lead author of the article. “This is a problem because it assumes we can put the burden on future generations — which is neither a realistic assumption nor is it morally acceptable from an intergenerational equity point of view.”
….The researchers present four archetype scenarios that incorporate a broader range of potential mitigation options. These include:
Major reliance on carbon dioxide removal in the future, the current archetype of many existing scenarios for achieving the 2°C or more stringent 1.5°C target.
Rapid decarbonization starting immediately, and halving every decade as proposed in a recent Science commentary coauthored by IIASA researchers.
Earlier implementation of carbon dioxide removal technologies, and phasing out by the end of the century
Consistent implementation of carbon dioxide removal from now until the end of the century.
Under all these scenarios, current country commitments under the Paris Agreement would not be sufficient to achieve the required cuts, the researchers say…
….IIASA researcher Fabian Wagner, another study coauthor adds, “In this paper we have shown that negative emission technologies may not only be an asset but also an economic burden if not deployed with care. We as scientists need to be careful when we communicate to policymakers about how realistic different scenarios might be. When we present scenarios that require the world to convert an amount of land equivalent to all today’s cropland to energy plantations, alarm bells should go off.”
Michael Obersteiner, Johannes Bednar, Fabian Wagner, Thomas Gasser, Philippe Ciais, Nicklas Forsell, Stefan Frank, Petr Havlik, Hugo Valin, Ivan A. Janssens, Josep Peñuelas, Guido Schmidt-Traub. How to spend a dwindling greenhouse gas budget. Nature Climate Change, 2018; 8 (1): 7 DOI: 10.1038/s41558-017-0045-1
New research predicts a significantly drier world if global warming reaches 2ºC. Over a quarter of the world’s land could become significantly drier and the change would cause an increased threat of drought and wildfires.
The change would cause an increased threat of drought and wildfires.
But limiting global warming to under 1.5C would dramatically reduce the fraction of the Earth’s surface that undergoes such changes. Areas which would most benefit from keeping warming below 1.5ºC include Central America, Southern Europe, Southern Australia, parts of South East Asia, and Southern Africa.
…Dr Chang-Eui Park….one of the authors of the study, said: “Aridification is a serious threat because it can critically impact areas such as agriculture, water quality, and biodiversity. It can also lead to more droughts and wildfires — similar to those seen raging across California.
“Another way of thinking of the emergence of aridification is a shift to continuous moderate drought conditions, on top of which future year-to-year variability can cause more severe drought.