In the extreme
The Fiscal Cost of Hurricanes: Disaster Aid Versus Social Insurance
Tatyana Deryugina
NBER Working Paper, May 2016
Abstract:
Little is known about the fiscal costs of natural disasters, especially regarding social safety nets that do not specifically target extreme weather events. This paper shows that US hurricanes lead to substantial increases in non-disaster government transfers, such as unemployment insurance and public medical payments, in affected counties in the decade after a hurricane. The present value of this increase significantly exceeds that of direct disaster aid. This implies, among other things, that the fiscal costs of natural disasters have been significantly underestimated and that victims in developed countries are better insured against them than previously thought.
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Motivated Recall in the Service of the Economic System: The Case of Anthropogenic Climate Change
Erin Hennes et al.
Journal of Experimental Psychology: General, June 2016, Pages 755-771
Abstract:
The contemporary political landscape is characterized by numerous divisive issues. Unlike many other issues, however, much of the disagreement about climate change centers not on how best to take action to address the problem, but on whether the problem exists at all. Psychological studies indicate that, to the extent that sustainability initiatives are seen as threatening to the socioeconomic system, individuals may downplay environmental problems in order to defend and protect the status quo. In the current research, participants were presented with scientific information about climate change and later asked to recall details of what they had learned. Individuals who were experimentally induced (Study 1) or dispositionally inclined (Studies 2 and 3) to justify the economic system misremembered the evidence to be less serious, and this was associated with increased skepticism. However, when high system justifiers were led to believe that the economy was in a recovery, they recalled climate change information to be more serious than did those assigned to a control condition. When low system justifiers were led to believe that the economy was in recession, they recalled the information to be less serious (Study 3). These findings suggest that because system justification can impact information processing, simply providing the public with scientific evidence may be insufficient to inspire action to mitigate climate change. However, linking environmental information to statements about the strength of the economic system may satiate system justification needs and break the psychological link between proenvironmental initiatives and economic risk.
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Shutting Down the Thermohaline Circulation
David Anthoff, Francisco Estrada & Richard Tol
American Economic Review, May 2016, Pages 602-606
Abstract:
Past climatic changes were caused by a slowdown of the thermohaline circulation. We use results from experiments with three climate models to show that the expected cooling due to a slowdown of the thermohaline circulation is less in magnitude than the expected warming due to increasing greenhouse gas concentrations. The integrated assessment model FUND and a meta-analysis of climate impacts are used to evaluate the change in human welfare. We find modest but by and large positive effects on human welfare since a slowdown of the thermohaline circulation implies decelerated warming.
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Economic Effects of an Ocean Acidification Catastrophe
Stephen Colt & Gunnar Knapp
American Economic Review, May 2016, Pages 615-619
Abstract:
We assess the potential magnitude of the economic effects of an ocean acidification (OA) catastrophe by focusing on marine ecosystem services most likely to be affected. It is scientifically plausible that by 2200 OA could cause a complete collapse of marine capture fisheries, complete destruction of coral reefs, and significant rearrangement of marine ecosystems. Upper-bound values for losses from the first two effects range from 97 to 301 billion 2014 dollars per year (0.09 - 0.28% of current world GDP). We argue that aquaculture output would not be reduced, due to the high potential for adaptation by this young industry.
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Tracking global carbon revenues: A survey of carbon taxes versus cap-and-trade in the real world
Jeremy Carl & David Fedor
Energy Policy, September 2016, Pages 50–77
Abstract:
We investigate the current use of public revenues which are generated through both carbon taxes and cap-and-trade systems. More than $28.3 billion in government “carbon revenues” are currently collected each year in 40 countries and another 16 states or provinces around the world. Of those revenues, 27% ($7.8 billion) are used to subsidize “green” spending in energy efficiency or renewable energy; 26% ($7.4 billion) go toward state general funds; and 36% ($10.1 billion) are returned to corporate or individual taxpayers through paired tax cuts or direct rebates. Cap-and-trade systems ($6.57 billion in total public revenue) earmark a larger share of revenues for “green” spending (70%), while carbon tax systems ($21.7 billion) more commonly refund revenues or otherwise direct them towards government general funds (72% of revenues). Drawing from an empirical dataset, we also identify various trends in systems’ use of “carbon revenues” in terms of the total revenues collected annually per capita in each jurisdiction and offer commensurate qualitative observations on carbon policy design choices.
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Greening of the Earth and its drivers
Zaichun Zhu et al.
Nature Climate Change, forthcoming
Abstract:
Global environmental change is rapidly altering the dynamics of terrestrial vegetation, with consequences for the functioning of the Earth system and provision of ecosystem services. Yet how global vegetation is responding to the changing environment is not well established. Here we use three long-term satellite leaf area index (LAI) records and ten global ecosystem models to investigate four key drivers of LAI trends during 1982–2009. We show a persistent and widespread increase of growing season integrated LAI (greening) over 25% to 50% of the global vegetated area, whereas less than 4% of the globe shows decreasing LAI (browning). Factorial simulations with multiple global ecosystem models suggest that CO2 fertilization effects explain 70% of the observed greening trend, followed by nitrogen deposition (9%), climate change (8%) and land cover change (LCC) (4%). CO2 fertilization effects explain most of the greening trends in the tropics, whereas climate change resulted in greening of the high latitudes and the Tibetan Plateau. LCC contributed most to the regional greening observed in southeast China and the eastern United States. The regional effects of unexplained factors suggest that the next generation of ecosystem models will need to explore the impacts of forest demography, differences in regional management intensities for cropland and pastures, and other emerging productivity constraints such as phosphorus availability.
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Price Regulation and Environmental Externalities: Evidence from Methane Leaks
Catherine Hausman & Lucija Muehlenbachs
NBER Working Paper, May 2016
Abstract:
Price regulations are widely used to reduce inefficiencies from natural monopolies, but they can introduce other inefficiencies, such as the failure to cost-minimize. We examine a previously unstudied distortion in the natural gas distribution sector that allows firms to pass the cost of lost gas on to their customers. We show that firms abate leaks below what is theoretically optimal for a private firm – expenditure on abatement is well below the cost of lost gas. Additionally, natural gas, primarily composed of methane, is both explosive and a potent greenhouse gas. Thus the climate impacts of leaked methane greatly exacerbate the inefficiencies created by imperfect price regulation.
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Global trends in wildfire and its impacts: Perceptions versus realities in a changing world
Stefan Doerr & Cristina Santín
Philosophical Transactions of the Royal Society: Biological Sciences, 5 June 2016
Abstract:
Wildfire has been an important process affecting the Earth's surface and atmosphere for over 350 million years and human societies have coexisted with fire since their emergence. Yet many consider wildfire as an accelerating problem, with widely held perceptions both in the media and scientific papers of increasing fire occurrence, severity and resulting losses. However, important exceptions aside, the quantitative evidence available does not support these perceived overall trends. Instead, global area burned appears to have overall declined over past decades, and there is increasing evidence that there is less fire in the global landscape today than centuries ago. Regarding fire severity, limited data are available. For the western USA, they indicate little change overall, and also that area burned at high severity has overall declined compared to pre-European settlement. Direct fatalities from fire and economic losses also show no clear trends over the past three decades. Trends in indirect impacts, such as health problems from smoke or disruption to social functioning, remain insufficiently quantified to be examined. Global predictions for increased fire under a warming climate highlight the already urgent need for a more sustainable coexistence with fire. The data evaluation presented here aims to contribute to this by reducing misconceptions and facilitating a more informed understanding of the realities of global fire.
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Electric utilities and American climate policy: Lobbying by expected winners and losers
Sung Eun Kim, Johannes Urpelainen & Joonseok Yang
Journal of Public Policy, June 2016, Pages 251-275
Abstract:
When and why do individual companies lobby on environmental policies? Given the structural strength of business interests, the answer to this question is important for explaining policy. However, evidence on the strategic lobbying behaviour of individual companies remains scarce. We use data from lobbying disclosure reports on all major climate bills introduced during the 111th Congress (2009–2010). We then link the lobbying disclosure reports to detailed data on the fuel choices of all electric utilities in the United States along with socioeconomic, institutional and political data from the states where the utilities operate. The expected winners (renewable energy, natural gas users) from climate policy are much more likely to lobby individually on federal legislation than the expected losers (coal users). We find that expected winners lobby for specific provisions and rents as a private good, whereas expected losers concentrate their efforts on collective action through trade associations and committees to prevent climate legislation. The results suggest that the supporters of climate policy believed the probability of federal climate legislation to be nontrivial.
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Poorest countries experience earlier anthropogenic emergence of daily temperature extremes
Luke Harrington et al.
Environmental Research Letters, May 2016
Abstract:
Understanding how the emergence of the anthropogenic warming signal from the noise of internal variability translates to changes in extreme event occurrence is of crucial societal importance. By utilising simulations of cumulative carbon dioxide (CO2) emissions and temperature changes from eleven earth system models, we demonstrate that the inherently lower internal variability found at tropical latitudes results in large increases in the frequency of extreme daily temperatures (exceedances of the 99.9th percentile derived from pre-industrial climate simulations) occurring much earlier than for mid-to-high latitude regions. Most of the world's poorest people live at low latitudes, when considering 2010 GDP-PPP per capita; conversely the wealthiest population quintile disproportionately inhabit more variable mid-latitude climates. Consequently, the fraction of the global population in the lowest socio-economic quintile is exposed to substantially more frequent daily temperature extremes after much lower increases in both mean global warming and cumulative CO2 emissions.
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Disruption of the European climate seasonal clock in a warming world
Christophe Cassou & Julien Cattiaux
Nature Climate Change, June 2016, Pages 589–594
Abstract:
Temperatures over Europe are largely driven by the strength and inland penetration of the oceanic westerly flow. The wind influence depends on season: blocked westerlies, linked to high-pressure anomalies over Scandinavia, induce cold episodes in winter but warm conditions in summer. Here, we propose to define the onset of the two seasons as the calendar day on which the daily circulation/temperature relationship switches sign. We have assessed this meteorologically based metric using several observational data sets and we provide evidence for an earlier onset of the summer date by ~10 days between the 1960s and 2000s. Results from a climate model show that internal variability alone cannot explain this calendar advance. Rather, the earlier onset can be partly attributed to anthropogenic forcings. The modification of the zonal advection due to earlier disappearance of winter snow over Eastern Europe, which reduces the degree to which climate has continental properties, is mainly responsible for the present-day and near-future advance of the summer date in Western Europe. Our findings are in line with phenological-based trends (earlier spring events) reported for many living species over Europe for which we provide an alternative interpretation to the traditionally evoked local warming effect. Based on the Representative Concentration Pathway (RCP) 8.5 scenario, which assumes that greenhouse gas emissions continue to rise throughout the twenty-first century, a summer advance of ~20 days compared with pre-industrial climate is expected by 2100, whereas no clear signal arises for winter onset.
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Elmar Kriegler et al.
Climatic Change, May 2016, Pages 7-22
Abstract:
We investigate the extent to which future energy transformation pathways meeting ambitious climate change mitigation targets depend on assumptions about economic growth and fossil fuel availability. The analysis synthesizes results from the RoSE multi-model study aiming to identify robust and sensitive features of mitigation pathways under these inherently uncertain drivers of energy and emissions developments. Based on an integrated assessment model comparison exercise, we show that economic growth and fossil resource assumptions substantially affect baseline developments, but in no case they lead to the significant greenhouse gas emission reduction that would be needed to achieve long-term climate targets without dedicated climate policy. The influence of economic growth and fossil resource assumptions on climate mitigation pathways is relatively small due to overriding requirements imposed by long-term climate targets. While baseline assumptions can have substantial effects on mitigation costs and carbon prices, we find that the effects of model differences and the stringency of the climate target are larger compared to that of baseline assumptions. We conclude that inherent uncertainties about socio-economic determinants like economic growth and fossil resource availability can be effectively dealt with in the assessment of mitigation pathways.
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Has Arctic Sea Ice Loss Contributed to Increased Surface Melting of the Greenland Ice Sheet?
Jiping Liu et al.
Journal of Climate, May 2016, Pages 3373–3386
Abstract:
In recent decades, the Greenland ice sheet has experienced increased surface melt. However, the underlying cause of this increased surface melting and how it relates to cryospheric changes across the Arctic remain unclear. Here it is shown that an important contributing factor is the decreasing Arctic sea ice. Reduced summer sea ice favors stronger and more frequent occurrences of blocking-high pressure events over Greenland. Blocking highs enhance the transport of warm, moist air over Greenland, which increases downwelling infrared radiation, contributes to increased extreme heat events, and accounts for the majority of the observed warming trends. These findings are supported by analyses of observations and reanalysis data, as well as by independent atmospheric model simulations using a state-of-the-art atmospheric model that is forced by varying only the sea ice conditions. Reduced sea ice conditions in the model favor more extensive Greenland surface melting. The authors find a positive feedback between the variability in the extent of summer Arctic sea ice and melt area of the summer Greenland ice sheet, which affects the Greenland ice sheet mass balance. This linkage may improve the projections of changes in the global sea level and thermohaline circulation.
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Future cost-competitive electricity systems and their impact on US CO2 emissions
Alexander MacDonald et al.
Nature Climate Change, May 2016, Pages 526–531
Abstract:
Carbon dioxide emissions from electricity generation are a major cause of anthropogenic climate change. The deployment of wind and solar power reduces these emissions, but is subject to the variability of the weather. In the present study, we calculate the cost-optimized configuration of variable electrical power generators using weather data with high spatial (13-km) and temporal (60-min) resolution over the contiguous US. Our results show that when using future anticipated costs for wind and solar, carbon dioxide emissions from the US electricity sector can be reduced by up to 80% relative to 1990 levels, without an increase in the levelized cost of electricity. The reductions are possible with current technologies and without electrical storage. Wind and solar power increase their share of electricity production as the system grows to encompass large-scale weather patterns. This reduction in carbon emissions is achieved by moving away from a regionally divided electricity sector to a national system enabled by high-voltage direct-current transmission.
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Adam Young et al.
Ecography, forthcoming
Abstract:
Boreal forests and arctic tundra cover 33% of global land surface and store an estimated 50% of total soil carbon. Because wildfire is a key driver of terrestrial carbon cycling, increasing fire activity in these ecosystems would likely have global implications. To anticipate potential spatiotemporal variability in fire-regime shifts, we modeled the spatially explicit 30-yr probability of fire occurrence as a function of climate and landscape features (i.e., vegetation and topography) across Alaska. Boosted regression tree (BRT) models captured the spatial distribution of fire across boreal forest and tundra ecoregions (AUC from 0.63-0.78 and Pearson correlations between predicted and observed data from 0.54-0.71), highlighting summer temperature and annual moisture availability as the most influential controls of historical fire regimes. Modeled fire-climate relationships revealed distinct thresholds to fire occurrence, with a nonlinear increase in the probability of fire above an average July temperature of 13.4 °C and below an annual moisture availability (i.e., P-PET) of approximately 150 mm. To anticipate potential fire-regime responses to 21st-century climate change, we informed our BRTs with Coupled Model Intercomparison Project Phase 5 climate projections under the RCP 6.0 scenario. Based on these projected climatic changes alone (i.e., not accounting for potential changes in vegetation), our results suggest an increasing probability of wildfire in Alaskan boreal forest and tundra ecosystems, but of varying magnitude across space and throughout the 21st century. Regions with historically low flammability, including tundra and the forest-tundra boundary, are particularly vulnerable to climatically induced changes in fire activity, with up to a fourfold increase in the 30-yr probability of fire occurrence by 2100. Our results underscore the climatic potential for novel fire regimes to develop in these ecosystems, relative to the past 6,000-35,000 years, and spatial variability in the vulnerability of wildfire regimes and associated ecological processes to 21st-century climate change.
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Todd Gerarden, Spencer Reeder & James Stock
NBER Working Paper, April 2016
Abstract:
Coal mined on federally managed lands accounts for approximately 40% of U.S. coal consumption and 13% of total U.S. energy-related CO2 emissions. The U.S. Department of the Interior is undertaking a programmatic review of federal coal leasing, including the climate effects of burning federal coal. This paper studies the interaction between a specific upstream policy, incorporating a carbon adder into federal coal royalties, and downstream emissions regulation under the Clean Power Plan (CPP). After providing some comparative statics, we present quantitative results from a detailed dynamic model of the power sector, the Integrated Planning Model (IPM). The IPM analysis indicates that, in the absence of the CPP, a royalty adder equal to the social cost of carbon could reduce emissions by roughly 3/4 of the emissions reduction that the CPP is projected to achieve. If instead the CPP is binding, the royalty adder would: reduce the price of tradeable emissions allowances, produce some additional emissions reductions by reducing leakage, and reduce wholesale power prices under a mass-based CPP but increase them under a rate-based CPP. A federal royalty adder increases mining of non-federal coal, but this substitution is limited by a shift to electricity generation by gas and renewables.