JP

Abstract: Air pollution is a major sustainability challenge – and future anthropogenic precursor and greenhouse gas emissions will greatly affect human well-being. While mitigating climate change can reduce air pollution both directly and indirectly, distinct policy levers can affect these two interconnected sustainability issues across a wide range of scenarios. We help to assess such issues by presenting a public Tool for Air Pollution Scenarios (TAPS) that can flexibly construct and assess a variety of climate and air quality emissions pathways through its coupling with socioeconomic modeling of climate change mitigation. In this study, we develop and implement TAPS with three components: recent global and fuel-specific anthropogenic emissions inventories, scenarios of emitting activities to 2100 from the MIT Economic Projection and Policy Analysis model (EPPA), and emissions intensity trends based on the latest Greenhouse Gas – Air Pollution Interactions and Synergies (GAINS) scenario data. An initial application shows that in scenarios with less climate and pollution policy ambition, near-term air quality improvements from existing policies are eclipsed by long-term emissions increases – particularly from industrial processes that combine sharp production growth with fewer pollution control levers in developing regions. Additional climate actions would substantially reduce energy-related air pollutant emissions (such as sulfur and nitrogen oxides), while further pollution controls are especially impactful for ammonia and organic carbon. Future TAPS applications could efficiently explore diverse regional and global policies that affect these emissions, using pollutant emissions results to drive global atmospheric chemical transport models to study the scenarios’ health impacts.

The latest United Nations IPCC Reports describe how limiting global warming to 1.5 degrees Celsius above pre-industrial levels can avert the worst impacts of climate change. That will require global emissions to drop by roughly half over the next decade and reach net-zero emissions near midcentury.

Abstract: Pathways for limiting global warming to 1.5° and 2°C generally involve net-zero greenhouse gas (GHG) emissions economy-wide near mid-century and halving emissions over the next decade. Updated pledges by countries and companies around the 2021 United Nations climate conference reflect this sense of urgency. The updated US pledge to reduce net emissions 50 to 52% by 2030 would represent a tripling of the pace of historical reductions.

We report on a six-model intercomparison of potential actions to reach the US target of at least 50% GHG reductions by 2030. This analysis helps identify which findings are more robust or uncertain given different model structures and input assumptions. Models highlight the central roles of clean electricity and electrification, the large scale of deployment needed relative to historical levels and scenarios with only current policies, and a range of benefits from near-term action.

The Colorado River and the Nile River are both undergoing dramatic transformations.

Throughout the last century and continuing today, major infrastructure developments have played a pivotal role in shaping the regional economies, livelihoods and environmental conditions of these two critical transboundary river systems. Our growing dependencies on these finite renewable resources are driven by population growth and economic expansion, but are being increasingly challenged by water scarcity that is partly driven by climate change.

Open to the MIT Community only

The MIT Joint Program on the Science and Policy of Global Change and MIT Laboratory for Aviation and the Environment invite you to join us at the seminar “Affordable Direct Air Capture: Myth or Reality?"

The seminar will be held in person (MIT Room 35-225) and online (via Zoom) on Thursday, May 26, 2022 at 1:00-2:30pm (US Eastern Time).

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