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Climate change is increasing the number of winter days with minimum temperatures above freezing across the Northern Hemisphere, leading to a reduction in snow cover and freshwater supplies. In the contiguous U.S., annual snowfall has decreased at 64% of 2,041 stations since 1970, and snow-derived freshwater in the western U.S. has fallen by 15-30% since 1955, with a further 25% decline projected by 2050.

The document outlines a methodology for estimating GHG emissions reductions achievable through land use reform in the US. It projects that over 13 million new housing units will be needed by 2033 to address population growth and existing shortages. By comparing a 'business as usual' scenario with a 'low VMT' scenario—where 90% of new housing is placed in the 90th percentile lowest VMT areas of each state—the analysis calculates potential savings in direct tailpipe emissions, vehicle lifecycle emissions, and indirect emissions from building energy, embodied carbon, and the loss of natural land carbon sinks.

The document details how a warming climate will increase the frequency and severity of heat waves and heavy precipitation in the Midwest, leading to higher mortality, infrastructure damage, and agricultural losses. It highlights specific risks to the Great Lakes shipping industry due to falling water levels and the threat to public health from water-borne diseases and combined sewer overflows in cities like Chicago and Milwaukee.

Since 1970, the Northeast has seen an average temperature increase of 2°F, leading to longer growing seasons and reduced snowpack. Future high-emissions scenarios project further warming, significant reductions in winter snow seasons, and increased frequency of extreme heat and flooding. These changes threaten the dairy and fruit industries, particularly cranberries, and risk substantial damage to coastal infrastructure in cities like New York and Boston. Additionally, the region's $7.6 billion winter recreation industry and specific fisheries, such as cod and lobster, face disruption due to warming waters and reduced snow cover.

The Southwest is projected to warm by 4-6°F under lower-emissions and 7-10°F under higher-emissions scenarios by the end of the century. The region faces severe water scarcity, expanding deserts, and reduced runoff, particularly in the Colorado River system. Public health risks include increased heat-related deaths in Los Angeles and worsening air quality. Economic threats include reduced yields for California specialty crops, diminished ski resort profitability due to snowpack loss, and reduced aircraft freight capacity at high-altitude airports like Phoenix and Denver. Biodiversity is critically threatened, especially in the Madrean Pine-Oak Woodlands, while mountain ecosystems face range reductions and reproductive failures in wildflowers due to earlier snowmelt and spring frosts.

The document outlines a strategy for the United States to reduce greenhouse gas emissions, stating that a 26 percent reduction below 2005 levels by 2025 is achievable through a comprehensive approach including the Clean Power Plan. It identifies the power sector as the primary opportunity for reductions, potentially reaching 30 percent by 2025 if policies are strengthened or renewable costs decline. For longer-term goals, the paper argues that Congressional action, specifically a national carbon price, could enable reductions of 40-42 percent by 2030 and 50-53 percent by 2040.

The world faces a 69 percent gap between 2006 crop calories and those required by 2050 for a population of 9.6 billion. Closing this gap through production alone would require increases exceeding those seen between 1962 and 2006. The document proposes a 'menu of solutions' categorized by reducing consumption, increasing production on existing land, and reducing emissions. Key strategies include cutting food loss and waste in half (reducing the gap by 20%), achieving replacement level fertility in sub-Saharan Africa (reducing the regional gap by 25%), and shifting 20% of future beef consumption to other proteins. It warns that aggressive bioenergy targets could widen the food gap to 100%.