PUBLICATIONS
FUTURE WARMING FROM GLOBAL FOOD CONSUMPTION
How can global food consumption contribute to future climate change? By how much can we reasonably reduce our impact?
In this project, we develop a global food consumption greenhouse gas emissions inventory separated by individual gas species and employ a reduced-complexity climate model in order to evaluate the future warming contributions associated with the global food sector and potential benefits from certain mitigation measures.
We find that global food consumption alone could add nearly 1°C to global average temperatures by 2100, pushing us past the 1.5°C and approaching the 2°C temperature goals established by the Paris Agreement. Seventy five percent of this warming is driven by foods that are high sources of methane, namely meat, dairy, and rice. However, over 55% of this anticipated warming can be avoided through simultaneous improvements to production practices, decarbonization of the energy used in food production, the universal adoption of a medically recommended diet, and retail- and consumer-level food waste reductions.
Ivanovich, C., Sun, T., Gordon, D., and Ocko, I., 2023. Future warming from global food consumption, Nature Climate Change, 13, 297–302. https://doi.org/10.1038/s41558-023-01605-8
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Associated interviews and news coverage includes:
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INTRASEASONAL VARIABILITY OF EXTREME HUMID HEAT
Understanding when and why extreme humid heat occurs is essential for informing public health efforts protecting against heat stress. This analysis works to improve our understanding of humid heat variability in two at-risk regions, the Persian Gulf and South Asia. By exploring how subseasonal oscillations affect daily extreme events, this analysis helps bridge the prediction gap between weather and climate. We find that extreme humid heat is more than twice as likely during specific phases of these oscillations than in others. Extremes depend to different extents upon combinations of above-average temperature and humidity. This new knowledge of the regional drivers of humid heat variability is important to better prepare for the increasingly widespread health and socioeconomic impacts of heat stress.
Ivanovich, C., Anderson, W., Horton, R., Raymond, C., and Sobel, A, 2022. Influence of Intraseasonal Oscillations on Extreme Wet Bulb Temperature in the Persian Gulf and South Asia, Journal of Climate, 35(13), 4309-4329. https://doi.org/10.1175/JCLI-D-21-0488.1
CLIMATE IMPACT OF INTERNATIONAL SHIPPING AND AVIATION
While individual countries work to achieve and strengthen their nationally determined contributions (NDCs) to the Paris Agreement, the growing emissions from two economic sectors remain largely outside most countries' NDCs: international shipping and international aviation. Reducing emissions from these sectors is particularly challenging because the adoption of any policies and targets requires the agreement of a large number of countries. However, the International Maritime Organization (IMO) and the International Civil Aviation Organization (ICAO) have recently announced strategies to reduce carbon dioxide (CO2) emissions from their respective sectors. Here we provide information on the climate benefits of these proposed measures, along with related potential measures. Given that the global average temperature has already risen 1 ∘C above preindustrial levels, there is only 1.0 or 0.5 ∘C of additional “allowable warming” left to stabilize below the 2 or 1.5 ∘C thresholds, respectively. We find that if no actions are taken, CO2 emissions from international shipping and aviation may contribute roughly equally to an additional combined 0.12 ∘C to global temperature rise by end of century – which is 12 % and 24 % of the allowable warming we have left to stay below the 2 or 1.5 ∘C thresholds (1.0 and 0.5 ∘C), respectively. However, stringent mitigation measures may avoid over 85 % of this projected future warming from the CO2 emissions from each sector. Quantifying the climate benefits of proposed mitigation pathways is critical as international organizations work to develop and meet long-term targets.
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Ivanovich, C., Ocko, I., Piris-Cabezas, P., and A. Petsonk, 2019. “Climate benefits of proposed carbon dioxide mitigation strategies for international shipping and aviation” Atmospheric Chemistry and Physics, 19, 14949–14965. https://doi.org/10.5194/acp-19-14949-2019