CAS: Earth & Environment: Datasets
Permanent URI for this collection
Browse
Recent Submissions
Item Energy price volatility affects decisions to purchase energy using capital: motor vehicles(Energy Economics, 2023-07-31) Kaufmann, RobertI investigate how energy price volatility affects consumer decisions to purchase durable, energy using capital, motor vehicles. A cointegrating vector autoregression (CVAR) model indicates that; (1) high price volatility reduces the negative effect of motor gasoline prices on monthly purchases of motor vehicles, (2) consumers consider passenger cars to be an inferior good and this drives the substitution of light trucks for passenger cars, (3) the own price elasticity of demand for vehicles is about -0.3, which is consistent with estimates used to justify The Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule for Models Years 2021-2026 Passenger Cars and Light Trucks. Simulating the CVAR model indicates that implementing an energy tax rapidly or during a period of low price volatility has a greater effect on motor vehicle sales than implementing the same tax slowly or during a period of high price volatility. Together these results suggest that more research should focus on how energy price volatility affects consumer decisions to purchase energy using capital.Item Social and Environmental Events Disrupt the Relation Between Motor Gasoline Prices and Market Fundamentals(2023-07-31) Kaufmann, Robert; Schroer, ColterAfter the Russian invasion of Ukraine, higher prices for motor gasoline re-ignited debate about price discovery; do market fundamentals largely determine motor gasoline prices. We evaluate the degree to which market fundamentals, as proxied by prices for crude oil, taxes on motor gasoline, inventories of crude oil and motor gasoline, and refinery utilization rates, can account for prices of motor gasoline. During most of the 2010 - 2022 sample, these proxies for market fundamentals account for weekly changes in the price for motor gasoline. But a saturation indicator procedure identifies weeks after the Russian invasion of Ukraine, Hurricane Harvey, and the start of the Covid-19 pandemic when prices for crude oil, taxes on motor gasoline, inventories of crude oil and motor gasoline, and refinery utilization rates fail to account for weekly changes in the price of motor gasoline in a statistically significant manner. During these weeks, the price of motor gasoline rises by up to $0.25 per gallon relative to that implied by market fundamentals, which increased expenditures on motor gasoline $10 to $72 per licensed driver.Item Dataset for: Implications of sea breezes on air quality monitoring in a coastal urban environment, evidence from high resolution modeling of NO2 and O3Geddes, Jeffrey; Wang, BoThis data contains observations and chemical transport model output relevant to an analysis of sea breeze impacts on local air quality in Boston. Model output are from a summer 2019 WRF-Chem simulation over the Northeast US, including the greater Boston region. Observational assets were compiled in order to evaluate the model performance.Item Isoprene and soil NOx impacts on nonattainment ozone from GEOS-CHem(2022) Geddes, JeffreyOzone (O3) is a criteria air pollutant that continues to pose a threat to more than one hundred million Americans each year, despite progress in regulating precursor emissions. In many O3-polluted areas, the role of natural emissions of isoprene in the production of ground-level O3 has been well recognized, but this chemistry depends strongly on local anthropogenic emissions which have been changing rapidly. We use an updated estimate of anthropogenic emissions to demonstrate that many areas that remain in nonattainment of the federally mandated O3 standard are now much less sensitive to natural isoprene emissions, with biogenic nitrogen oxide emissions from soils becoming more and more important. The role of these soil emissions on O3 in nonattainment areas has not been well characterized, but, as we show in our companion article in JGR-Atmospheres, this will become increasingly necessary for good O3 policy in nonattainment areas.Item The multiplier effect of endogenous technical change accelerates the transition to photovoltaic cells(2022) Tendler, Anita C.; Kaufmann, Robert K.Abating emissions of carbon dioxide depends in part on how quickly the levelized cost of electricity (LCOE) from photovoltaic cells (PV) achieves grid parity without policy interventions. Reaching this threshold is accelerated by learning by doing, which reduces the LCOE generated by PV and increases installed capacity. Here, we expand previous estimates of unidirectional (Capacity → Price) learning curves to include the effect of prices on capacity by estimating a cointegrating vector autoregression (CVAR) model, which can capture a simultaneous relation between price and capacity. Results indicate that the simultaneous relation between price and capacity increases the estimate for the learning rate and creates a multiplier that amplifies static effects by nearly a factor of ten. This same multiplier effect enhances the ability of policies, such as a carbon tax, to lower the costs of PV, increase capacity, and lower carbon emissions. Together, these results suggest that grid parity is closer than indicated by unidirectional learning curves.Item Contemporary land use and land cover change impacts on global air qualityGeddes, Jeffrey; Wong, AnthonyOur work explores the impact of two important dimensions of land system changes, land use and land cover change (LULCC) and direct agricultural reactive nitrogen (Nr) emissions from soils, on ozone (O3) and fine particulate matter (PM2.5) air quality over contemporary (1992 to 2014) time scales. We account for LULCC and agricultural Nr emissions changes with consistent remote sensing products and new global emission inventories, respectively, estimating their impacts on global surface O3 and PM2.5 concentrations and Nr deposition using the GEOS-Chem global chemical transport model. This repository contains the GEOS-Chem configuration files for each of our five simulations, in order to be able to reproduce identical simulation experiments.Item Non-stomatal pathways in ozone deposition, Wong et al. (Submitted 2021)(2021) Geddes, Jeffrey A.; Wong, AnthonyDry deposition is one of the driving factors behind ozone-meteorology relationships. We examine the response of ozone deposition to heat and dry anomalies using three long-term co-located ecosystem-scale carbon dioxide, water vapor and ozone flux measurement records. We find that, as expected, canopy stomatal conductance generally decreases during days with dry air or soil. However, during hot days, concurrent increases in non-stomatal conductance are inferred at all three sites, which may be related to several temperature-sensitive processes not represented in the current generation of big-leaf models. This may offset the reduction in stomatal conductance, leading to smaller net reduction, or even net increase, in total deposition velocity. We find the response of deposition velocity to soil dryness may be related to its impact on photosynthetic activity, though considerable variability exists. Our findings emphasize the need for better understanding and representation of non-stomatal ozone deposition processes.Item Air quality in a coastal urban area, Geddes et al. (Submitted, 2021)(2021) Geddes, Jeffrey A.We present an analysis of sea breeze conditions for the Boston region, and examine their impact on the concentration of local air pollutants over the past decade. Sea breezes occur about one third of the days during the summer, and play an important role in the spatial distribution and temporal evolution of NO2 and O3 across the urban area. Mornings preceding a sea breeze are characterized by low horizontal wind speeds, low background O3, and an accumulation of local primary emissions. Air pollution is recirculated inland during sea breezes, frequently coinciding with the highest O3 measured at the urban center. We use “Ox” (= NO2 + O3) to account for temporary O3 suppression by NO, and find large horizontal gradients (differences in Ox greater than 30 ppb across less than 15 km), which are not observed on otherwise westerly- or easterly-prevailing days. This implies a challenge in surface monitoring networks to adequately represent the spatial variability of secondary air pollution in coastal urban areas. We investigate satellite-based climatologies of tropospheric NO2, and find evidence of selection biases due to cloud conditions, but show that sea breeze days are well observed due to the fair weather conditions generally associated with these events. The fine scale of the sea breeze in Boston is not reliably represented by meteorological reanalyses products commonly used in chemical transport models required to provide inputs for the satellite-based retrievals. This implies a higher systematic error in the operational retrievals on sea breeze days compared to other days.Item Data and code for: Feedbacks among electric vehicle adoption, charging, and the cost and installation of rooftop solar(2020-10) Kaufmann, Robert K.; Newberry, Derek; Xin, Chen; Gopal, SucharitaIdentifying feedback loops in consumer behaviors is important to develop policies to accentuate desired behavior. Here, we use Granger causality to provide empirical evidence for feedback loops among four important components of a low-carbon economy. One loop includes the cost of installing rooftop solar (Cost) and the installation of rooftop solar (PV); this loop is likely generated by learning by doing and reductions in the levelized cost of electricity. The second includes the purchase of electric vehicles (EV) and the installation of rooftop solar that is likely created by environmental complementarity. Finally, we address whether installing charging stations enhances the purchase of electric vehicles and vice versa; surprisingly, there is no evidence for a causal relation in either direction. Together, these results suggest ways to modify existing policy in ways that could trigger the Cost ↔PV ↔EV feedback loops and accelerate the transition to carbon free technologies.Item Data for: Understanding glacial cycles: a multivariate disequilibrium approach(2020) Kaufmann, Robert K.; Pretis, FelixWe find a consistent relation between orbital geometry and components of the climate system by returning to Milankovitch’s original hypothesis and focusing on the well-established physical concepts of an equilibrium state, disequilibrium from that state, and adjustment towards equilibrium. These mechanisms imply that the state of the climate system at any time depends on; (1) the state of the climate system in the previous period, (2) the degree to which this previous state is out-of-equilibrium with orbital geometry, and (3) the rate at which the climate system adjusts towards equilibrium. We evaluate this explanation by running experiments with a statistical model of climate that explicitly represents equilibria among variables and their movements towards equilibrium. Results indicate that; (1) skipped obliquity/precession beats are an artifact of ignoring adjustments towards an equilibrium state, (2) accounting for equilibrium and adjustments to equilibrium can account for all phases of the glacial cycle, and (3) glacial cycles are generated by adjustments to equilibrium relations between orbital geometry and climate and among components of the climate system. Together, these results suggest a new approach to understanding glacial cycles that is based on models which include a rich set of equilibria and adjustments to equilibria for a full suite of climate variables simulated over long periods.Item Data and code for: Testing Hypotheses About Glacial Dynamics and the Stage 11 Paradox Using a Statistical Model of Paleo-Climate(2020-04) Kaufmann, Robert K.; Pretis, FelixTo test hypotheses about glacial dynamics, the Mid-Brunhes event, and the stage 11 paradox, we evaluate the ability of a statistical model to simulate climate during the previous ~800,000 years. Throughout this period, the model simulates the timing and magnitude of glacial cycles, including the saw-tooth pattern in which ice accumulates gradually and ablates rapidly, without nonlinearities or threshold effects. This suggests that nonlinearities and/or threshold effects do not play a critical role in glacial cycles. Furthermore, model accuracy throughout the previous ~800,000 years suggest that changes in glacial cycles associated with the Mid-Brunhes event, which occurs near the division between the out-of-sample period and the in-sample period, are not caused by changes in the dynamics of the climate system. Conversely, poor model performance during MIS stage 11 and Termination V is consistent with arguments that the ‘stage 11 paradox’ represents a mismatch between orbital geometry and climate. Statistical orderings of simulation errors indicate that periods of reduced accuracy start with significant reductions in the model’s ability to simulate carbon dioxide, non-sea-salt sodium, and non-sea-salt calcium. Their importance suggests that the stage 11 paradox is generated by changes in atmospheric and/or oceanic circulation that affect ocean ventilation of carbon dioxide.Item Sensitivity of global pasturelands to climate variation(2019) Stanimirova, Radost; Arévalo, Paulo; Kaufmann, Robert K.; Maus, Victor; Lesiv, Myroslava; Havlík, Petr; Friedl, Mark A.Pasturelands are globally extensive, sensitive to climate, and support livestock production systems that provide an essential source of food in many parts of the world. In this paper, we integrate information from remote sensing, global climate, and land use databases to improve understanding of the resilience and resistance of this ecologically vulnerable and societally-critical land use. To characterize the effect of climate on pastureland productivity, we analyze the relationship between satellite-derived vegetation index and gridded precipitation datasets at 1 to 6-month time lags. To account for the effects of different production systems, we stratify our analysis by agroecological zone and by rangeland-based versus mixed crop-livestock system. Results show that 14.5% of global pasturelands experienced statistically significant greening or browning trends over the 15-year study period, with the majority of these locations showing greening. In arid ecosystems, precipitation and lagged vegetation index anomalies explain up to 69% of variation in vegetation productivity in both crop-livestock and rangeland-based production systems. Livestock production systems in Australia are least resistant to contemporaneous and short-term precipitation anomalies, while arid livestock production systems in Latin America are least resilient to short-term vegetation greenness anomalies. More generally, large swaths of semi-arid global pasturelands show substantial sensitivity to variation in precipitation, and hence, are vulnerable to climate change. Because many arid regions of the world are projected to experience decreased total precipitation and increased precipitation variability in the coming decades, improved understanding regarding the sensitivity of pasturelands to the joint effects of climate change and production system is required to support sustainable land management in global pasturelands.