Energy futures
Temperatures, food riots, and adaptation: A long-term historical analysis of England
Alexander De Juan & Tim Wegenast
Journal of Peace Research, forthcoming
Abstract:
A large body of research indicates that environmental conditions can influence the risk of social unrest. However, we know little about how these effects may change in the long run. Are they likely to remain constant or do they change over time – for example as a consequence of human adaptation? To investigate this question, we rely on a disaggregated analysis of England over a period of more than 300 years. Combining data on geo-referenced food riots with reconstructed climate data, we first assess the impact of annual temperatures on social unrest over the period 1500–1817. We then use our long-term time-series dataset to assess the temporal heterogeneity of year-to-year associations between temperatures and social conflict. Our models show a substantive negative correlation between temperatures and food riots in the aggregate. This association, however, seems to be highly inconsistent over time and largely confined to the 18th century. In addition, we find evidence of decadal processes of adaptation: past exposure to adverse weather conditions dampens the effect of current exposure. Taken together, these findings underline the importance of considering temporal heterogeneities when assessing the climate-conflict nexus and caution against any simple extrapolations of observable present-day effects of environmental conditions into the future.
Climate change exacerbates hurricane flood hazards along US Atlantic and Gulf Coasts in spatially varying patterns
Reza Marsooli et al.
Nature Communications, August 2019
Abstract:
One of the most destructive natural hazards, tropical cyclone (TC)–induced coastal flooding, will worsen under climate change. Here we conduct climatology–hydrodynamic modeling to quantify the effects of sea level rise (SLR) and TC climatology change (under RCP 8.5) on late 21st century flood hazards at the county level along the US Atlantic and Gulf Coasts. We find that, under the compound effects of SLR and TC climatology change, the historical 100-year flood level would occur annually in New England and mid-Atlantic regions and every 1–30 years in southeast Atlantic and Gulf of Mexico regions in the late 21st century. The relative effect of TC climatology change increases continuously from New England, mid-Atlantic, southeast Atlantic, to the Gulf of Mexico, and the effect of TC climatology change is likely to be larger than the effect of SLR for over 40% of coastal counties in the Gulf of Mexico.
Observed climatic changes in West Virginia and opportunities for agriculture
Evan Kutta & Jason Hubbart
Regional Environmental Change, April 2019, Pages 1087–1099
Abstract:
Increasing variability in temperature and precipitation patterns is reducing the security of natural resources including food, water, and energy in many locations globally. Changes in climate are particularly relevant to the agricultural sector, given the increasing demand for food, less predictable water supplies, and more expensive energy. Among these challenges, however, are opportunities to improve human health with climate-conscious approaches to field crop production. Such opportunities may be emerging in historically productive areas in the Appalachian region of the United States including West Virginia that are often typified by food deserts. Long-term records of farm count, farm area, and crop yield data for West Virginia’s most valuable crops are presented relative to national averages to better understand emergent challenges and opportunities associated with local climate changes. Observed datasets of daily maximum temperature, minimum temperature, and precipitation for 18 climate observation sites in West Virginia dating back to at least 1930 were used to assess climatic trends between 1900 and 2016. To account for the regions’ complex physiography, daily data were averaged annually and spatially (all 18 sites). The maximum temperatures were shown to decrease significantly (− 0.78 °C/century; p = 0.001), whereas the minimum temperatures increased significantly (0.44 °C/century; p = 0.017), and precipitation increased (25.4 mm/century). Additionally, intra-annual variance of maximum temperatures decreased (− 0.22 °C/century), minimum temperatures increased significantly (0.39 °C/century; p = 0.041), and precipitation increased (25.4 mm/century). Observed climate trends suggest that local and regional changes in land-atmosphere interactions may result in a wetter and more temperate Appalachian climate characterized by longer growing seasons that may be supportive of a broader range of crops. Results suggest that strategically expanding local agriculture to adapt to changing climate could simultaneously improve human health and socioeconomic status in West Virginia, the broader Appalachian region, and other similar physiographic locations globally.
Adverse effects of rising interest rates on sustainable energy transitions
Tobias Schmidt et al.
Nature Sustainability, September 2019, Pages 879–885
Abstract:
Increasing the use of renewable energy (RE) is a key enabler of sustainable energy transitions. While the costs of RE have substantially declined in the past, here we show that rising interest rates (IRs) can reverse the trend of decreasing RE costs, particularly in Europe with its historically low IRs. In Germany, IRs recovering to pre-financial crisis levels in 5 years could add 11% and 25% to the levelized cost of electricity for solar photovoltaics and onshore wind, respectively, with financing costs accounting for about one-third of total levelized cost of electricity. As fossil-fuel-based electricity costs are much less and potentially even negatively affected by rising IRs, the viability of RE investments would be markedly deteriorated. On the basis of these findings, we argue that rising IRs could jeopardize the sustainable energy transition and we propose a self-adjusting thermostatic policy strategy to safeguard against rising IRs.
Increased shear in the North Atlantic upper-level jet stream over the past four decades
Simon Lee, Paul Williams & Thomas Frame
Nature, 29 August 2019, Pages 639–642
Abstract:
Earth’s equator-to-pole temperature gradient drives westerly mid-latitude jet streams through thermal wind balance. In the upper atmosphere, anthropogenic climate change is strengthening this meridional temperature gradient by cooling the polar lower stratosphere and warming the tropical upper troposphere, acting to strengthen the upper-level jet stream. In contrast, in the lower atmosphere, Arctic amplification of global warming is weakening the meridional temperature gradient, acting to weaken the upper-level jet stream. Therefore, trends in the speed of the upper-level jet stream represent a closely balanced tug-of-war between two competing effects at different altitudes. It is possible to isolate one of the competing effects by analysing the vertical shear — the change in wind speed with height — instead of the wind speed, but this approach has not previously been taken. Here we show that, although the zonal wind speed in the North Atlantic polar jet stream at 250 hectopascals has not changed since the start of the observational satellite era in 1979, the vertical shear has increased by 15 per cent (with a range of 11–17 per cent) according to three different reanalysis datasets. We further show that this trend is attributable to the thermal wind response to the enhanced upper-level meridional temperature gradient. Our results indicate that climate change may be having a larger impact on the North Atlantic jet stream than previously thought. The increased vertical shear is consistent with the intensification of shear-driven clear-air turbulence expected from climate change, which will affect aviation in the busy transatlantic flight corridor by creating a more turbulent flying environment for aircraft. We conclude that the effects of climate change and variability on the upper-level jet stream are being partly obscured by the traditional focus on wind speed rather than wind shear.
Deliberate enhancement of rainfall using desert plantations
Oliver Branch & Volker Wulfmeyer
Proceedings of the National Academy of Sciences, 17 September 2019, Pages 18841-18847
Abstract:
Large-scale afforestation is increasingly being considered as a negative emissions method for sequestering large quantities of atmospheric CO2. At the same time, regional weather modification methods, like cloud seeding, are being used to counteract increasing water scarcity in arid regions. Large-scale sustainable desert agroforestry plantations can contribute to climate change mitigation and can also be used to modify regional climate, particularly rainfall. Climate impacts from plantations need to be well understood before considering implementation. Typically, impact studies are attempted at continental or global scales and use coarse-resolution models, which suffer from severe systematic errors. This is highly problematic because decision makers should only countenance geoengineering schemes like global afforestation if impacts are understood on the regional scale. We posit the necessity of using high-resolution regional models with sophisticated representations of land–atmosphere feedback and vegetation. This approach allows for studying desert plantations and the process chain leading to climate modification. We demonstrate that large-scale plantations enhance regional clouds and rainfall and derive an index for predicting plantation impacts. Thus, desert plantations represent a unique environmental solution via predictable regional weather modification and carbon storage.
China and India lead in greening of the world through land-use management
Chi Chen et al.
Nature Sustainability, February 2019, Pages 122–129
Abstract:
Satellite data show increasing leaf area of vegetation due to direct factors (human land-use management) and indirect factors (such as climate change, CO2 fertilization, nitrogen deposition and recovery from natural disturbances). Among these, climate change and CO2 fertilization effects seem to be the dominant drivers. However, recent satellite data (2000–2017) reveal a greening pattern that is strikingly prominent in China and India and overlaps with croplands world-wide. China alone accounts for 25% of the global net increase in leaf area with only 6.6% of global vegetated area. The greening in China is from forests (42%) and croplands (32%), but in India is mostly from croplands (82%) with minor contribution from forests (4.4%). China is engineering ambitious programmes to conserve and expand forests with the goal of mitigating land degradation, air pollution and climate change. Food production in China and India has increased by over 35% since 2000 mostly owing to an increase in harvested area through multiple cropping facilitated by fertilizer use and surface- and/or groundwater irrigation. Our results indicate that the direct factor is a key driver of the ‘Greening Earth’, accounting for over a third, and probably more, of the observed net increase in green leaf area. They highlight the need for a realistic representation of human land-use practices in Earth system models.
Higher Carbon Prices on Emissions Alone Will Not Deliver the Paris Agreement
Habiba Daggash & Niall Mac Dowell
Joule, forthcoming
Abstract:
Limiting global warming to 2°C by 2100 requires anthropogenic CO2 emissions to reach zero by 2070 and become negative afterwards; therefore, large-scale carbon dioxide removal (CDR) from the atmosphere is critical. We investigate the effectiveness of carbon prices in achieving the deep decarbonization needed in the power system. We find that if only CO2 emitters are penalized, increasing prices to the social cost of carbon is sufficient to achieve a decarbonized system in the medium-term but not maintain it in the long-term. Unless carbon pricing mechanisms are adapted to remunerate CDR services, CDR technologies are not deployed. Incentivizing CDR could mean that lower levels of carbon taxation are needed to meet the Paris Agreement, which in turn lowers electricity costs.
However, the deployment of CDR technologies could prolong the use of unabated fossil fuels in a carbon-constrained system, therefore, disincentives must be implemented to prevent this moral hazard from manifesting.
Projected declines in global DHA availability for human consumption as a result of global warming
Stefanie Colombo et al.
Ambio, forthcoming
Abstract:
Docosahexaenoic acid (DHA) is an essential, omega-3, long-chain polyunsaturated fatty acid that is a key component of cell membranes and plays a vital role in vertebrate brain function. The capacity to synthesize DHA is limited in mammals, despite its critical role in neurological development and health. For humans, DHA is most commonly obtained by eating fish. Global warming is predicted to reduce the de novo synthesis of DHA by algae, at the base of aquatic food chains, and which is expected to reduce DHA transferred to fish. We estimated the global quantity of DHA (total and per capita) currently available from commercial (wild caught and aquaculture) and recreational fisheries. The potential decrease in the amount of DHA available from fish for human consumption was modeled using the predicted effect of established global warming scenarios on algal DHA production and ensuing transfer to fish. We conclude that an increase in water temperature could result, depending on the climate scenario and location, in a ~ 10 to 58% loss of globally available DHA by 2100, potentially limiting the availability of this critical nutrient to humans. Inland waters show the greatest potential for climate-warming-induced decreases in DHA available for human consumption. The projected decrease in DHA availability as a result of global warming would disproportionately affect vulnerable populations (e.g., fetuses, infants), especially in inland Africa (due to low reported per capita DHA availability). We estimated, in the worst-case scenario, that DHA availability could decline to levels where 96% of the global population may not have access to sufficient DHA.
Media Coverage of Climate Change and Sustainable Product Consumption: Evidence from Hybrid Vehicle Market
Yubo Chen et al.
Journal of Marketing Research, forthcoming
Abstract:
As sustainable consumption becomes increasingly important, firms must better understand the drivers behind the consumption of these products. This article examines the effects of mass media in the context of the U.S. hybrid vehicle market. Drawing on monthly sales data, the authors provide evidence that the general coverage of climate change or global warming by major media outlets exerts an overall positive impact on the sales of hybrid vehicles. This impact mainly comes from the media reports that assert that climate change is occurring. In contrast, media coverage that either denies climate change or holds a neutral stance on the issue has little impact. The authors provide preliminary evidence that a social norm advocating for environmentally friendly consumption plays an important role in how media coverage affects consumer purchase. They provide implications for theory and practice and call for future research that examines the causal impact of media in general on consumer decisions, especially in domains that are crucial for the society.
Electricity market deregulation and environmental regulation: Evidence from U.S. nuclear power
Daniel Karney
Energy Economics, forthcoming
Abstract:
Nuclear power in the United States provides substantial electricity supply and thus this study replicates the finding in Davis and Wolfram (2012) that divestiture leads to a statistically significant and economically meaningful increase in nuclear power reactor output. Divestiture is the sale of generating assets from regulated, investor-owned utilities to independent power producers with the profit motive to increase output. The divestiture effect result is robust to specification choice and testing with an extended dataset containing additional years of observations. This study also finds the new result that reactor output increases via an indirect environmental policy mechanism. The environmental regulations considered occurred contemporaneously to the divestitures and thus provides a further robustness check on the divestiture effect result.