1864: George Perkins Marsh, considered by some to be America’s first environmentalist, publishes Man and Nature; or, Physical Geography as Modified by Human Action.
1872: President Ulysses Grant signs a law establishing Yellowstone as America's first national park.
1892: The Sierra Club is founded by adventurer and conservationist John Muir. Today the club has 3.5 million members and is one of the most influential environmental organizations in the United States.
1906: President Theodore Roosevelt signs the Antiquities Act, "the first general legal protection of cultural and natural resources in the United States".
1927: World human population reaches 2 billion.
1947: Writer and conservationist Marjory Stoneman Douglas publishes The Everglades: River of Grass, and leads a campaign to establish the Everglades National Park in Florida.
1962: Rachel Carson publishes Silent Spring; it becomes a New York Times bestseller, selling over 500,000 copies in 24 countries.
1969: The National Environmental Policy Act (NEPA), often called the "Magna Carta" of environmental laws, is drafted. NEPA requires federal agencies to evaluate the environmental consequences of their policies and outlines how environmental impact assessments should be carried out. Since becoming a law in 1970, NEPA has served as a model for similar policies in over 100 countries. Senator Gaylord Nelson (D-WI) proposes the idea for a “national teach-in on the environment”.
1970: The U.S. Congress passes the Clean Air Act of 1970, authorizing the government to control emissions from both stationary (industrial) sources and mobile sources. President Richard Nixon signs legislation creating the National Oceanic and Atmospheric Administration (NOAA) and the Environmental Protection Agency (EPA).
Following Sen. Nelson's proposal, the first U.S. "Earth Day" (also called International Mother Earth Day) is celebrated on April 22. Recognized as the birth of the modern environmental movement; over 20 million Americans from all walks of life participate in rallies.
1972: The insecticide DDT is banned from usage in the United States. Congress reorganizes the Federal Water Pollution Control Act into the Clean Water Act and passes it into law. The act limits pollutants in rivers, lakes and streams. The "Don't Make a Wave Committee" -- first formed in 1969 in Vancouver, Canada -- rebrands itself as Greenpeace. The sometimes-controversial organization supports research, lobbying and protest actions on a wide variety of environmental issues.
1973: Congress passes the Endangered Species Act, providing protection for threatened and endangered plants and animals and their habitats.
1974: The EPA begins a phaseout of lead from gasoline. Congress passes the Safe Drinking Water Act.
1990: Earth Day becomes a global event, with observances scheduled in over 140 countries. President George W. Bush signs the Clean Air Amendments into law.
1992: The Energy Star program is launched. To date, the program has saved companies and consumers over $450 billion in energy costs.
1995: Senator Gaylord Nelson receives the Presidential Medal of Freedom, twenty-five years after helping organize the first Earth Day celebration.
1997: Toyota begins selling the Prius, the first mass-produced hybrid-fuel automobile. (The new car will not become available in the US until 2000.)
2000: 184 countries help celebrate the 30th anniversary of Earth Day, focusing on “clean energy".
2005: The Kyoto Protocol, proposed in 1997, takes effect. 192 countries ratify the agreement, which commits them to reduce greenhouse gas emissions over a five-year period, 2008-2012.
2010: The Earth Day Network organizes a 40th anniversary Climate Rally at the National Mall in Washington, D.C.; 250,000 people attend. The 2010 theme is "New Energy for a New Era".
2011: World human population reaches 7 billion.
2016: The Paris Agreement on Climate Change is signed by over 120 countries, including the United States. Participants agree to plan and implement changes that will mitigate global warming, including reducing greenhouse gas emissions.
2017: The United States announces its withdrawal from the Paris Accord as of November 4, 2020. Volume I of the 4th National Climate Assessment, the Climate Science Special Report, is released. The U.S. Climate Action Plan (2013) is terminated.
2018: Volume II of the NCA is released, warning of increasingly negative impacts of climate change. Preliminary US data shows 2018 as the 14th warmest year on record; globally, it was the 4th warmest year based on measurements of both land- and sea-recorded temperatures.
2019: Senate bill S.47, the John D. Dingell Jr. Conservation, Management, and Recreation Act, becomes law. Provisions include making the Land and Water Conservation Fund permanent, permanently giving all fourth-graders free access to national parks, and more.
The Carbon cycle and atmospheric CO₂: natural variations, Archean to present Call number: QE516.5 .C37 1984
The Great ocean conveyor : discovering the trigger for abrupt climate change Call number: GC190.2 .B76 2010
The sea around us Call number: GC21 .C3 1961
Under the sea-wind; a naturalist's picture of ocean life  Call number: QH92 .C3
The silent world  Call number: QH91 .C6
Marjory Stoneman Douglas:
Hurricane Call number: QC945 .D6 1958
George Perkins Marsh:
Man and nature, or, Physical geography as modified by human action Call number: GF31 .M35 1864 ESL
In History of Science Collection
Senator Gaylord Nelson:
President Theodore Roosevelt:
The man who works with his hands : Address of President Roosevelt at the semi-centennial celebration of the founding of agricultural colleges in the United States, at Lansing, Mich., May 31, 1907 Government Documents: A 1.4:24
American bears : selections from the writings of Theodore Roosevelt Call number: SK295 .R66 1983