Report of the Topical Group on Environmental and Societal Impacts of Particle Physics for Snowmass 2021

Abstract

Report of the Topical Group on Environmental and Societal Impacts of Particle Physics for Snowmass 2021that human influence has warmed the atmosphere, ocean and land. Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred". The IPCC further states that "Global warming of 1.5 • C and 2 • C will be exceeded during the 21st century unless deep reductions in CO 2 and other greenhouse gas emissions occur in the coming decades." To limit the amount of warming, we will have to achieve significant reductions in CO 2 emissions, to the point of net-zero emissions, along with reductions in the production of other greenhouse gases (GHGs), in line with the goals of the Paris Agreement. The 6th IPCC assessment report estimates a total budget of 300 gigatons CO2e (CO 2 equivalent) emissions for an 83% chance to limit global warming to below 1.5 degrees Celsius. This amounts to about 1.1 t CO2e emissions per capita per year until 2050. This should be compared to current per capita per year emission rates of 14.2 tCO 2 in the United States. Significant reductions in carbon emissions must be achieved for the future health of the planet, and measures must be taken now rather than later to begin to limit the long-term impacts.The U.S is a crucial player in the climate agenda. It is the top producer and consumer of both oil and natural gas, it has the world's second largest number of coal-fired power plants, and fossil fuels contributed 63% to its overall electricity generation. On the other hand, it also has the largest nuclear and second largest renewable capacity in the world. Not only is the U.S. the second largest emitter of GHGs, but over the course of history it has cumulatively produced more than any other country. Its citizens have emissions footprints that are roughly three times the global average. The U.S also has a large impact on climate policy. For example, the success of the 2015 Paris agreement was due in significant part to the leadership demonstrated by the U.S. at that time. More recently, the current administration has submitted an updated Nationally Determined Contribution to cut greenhouse gas emissions 50-52% below 2005 levels by 2030 and has pledged to achieve net-zero emissions by "no later than 2050".Current and future activities in particle physics need to be considered in this context. The pursuit of particle physics requires substantial construction projects; the consumption of electricity in the operation of accelerators, detectors, and computing; the use of GHGs in particle detectors; and in some cases significant amounts of travel. All of these lead to the potential for particle physicists to have a carbon impact well above that of typical citizens, and thus particle physicists should be paying attention to the impacts of the discipline on the planet and seeking to reduce them. Just as our field currently demonstrates world leadership in international cooperation towards common goals, we can also demonstrate world leadership in this critical area that impacts the...