Landsat Brings Understanding to the Impact of Industrialization

In his 1963 book The Quiet Crisis, Interior Secretary Stewart Udall warned that industrialization and urban growth were draining America's natural resources: a nation at the height of wealth and power was losing its beauty and open space to ugliness, pollution, noise and blight. To Udall and others in the environmental movement, the planet suddenly seemed finite, and the United States needed to manage its resources better. He went on to urge that the country turn its remote-sensing technology toward Earth, to understand and document the consequences of human expansion. By 2019, 56 years later, Landsat satellites were doing exactly that.

Watching land change

From 438 miles up, Landsat sensors record one of the defining features of industrial growth: land being put to more profitable use.

• In Brazil, tropical forest is converted to soybean fields.
• In northern Alberta, open-pit mining of the tar sands strips the landscape to send oil to the United States.
• In the U.S. South, farmers turn marginal farmland into loblolly pine plantations. Landsat records the seedlings going in, can read the light from their canopies to help decide when to fertilize or spray herbicide, and, 15 to 25 years later, sees the mature trees harvested for the paper and pulp industries.

Near Fort McMurray, Alberta: Landsat 1 on August 20, 1974 (left), with little open-pit mining, and Landsat 8 on October 1, 2015 (right), with widespread mining of the tar sands. USGS.

According to Curtis Woodcock, a Boston University professor who chaired the USGS Landsat Science Team, examples like these show how Landsat helps us understand humanity's effect on the planet — both by providing a continuous baseline for tracking change over time and by making possible a global effort to change how resources and land are used.

Measuring forests and carbon

Under the United Nations Framework Convention on Climate Change, almost 200 countries have said they are willing to cut greenhouse gas emissions from fossil fuels and land-use change within their borders, and success can bring them financial rewards — so free Landsat data are an economical way to track progress, especially on deforestation. Trees store large amounts of carbon in their leaves, trunks and roots. According to the U.S. Forest Service, forests make up 80 to 90 percent of the nation's carbon sink and take up 10 to 15 percent of its carbon dioxide emissions. With Landsat data, the United States and other countries can show how much forest they have, how much is being degraded and how much replanted.

Without Landsat's historical record such comparisons would be hard. Woodcock likens Landsat to a free press for the Earth: an objective account of how mining, deforestation and every other change in land use — the good and the bad of industrial growth — are affecting the planet.

Landsat has, at least, helped end the "quiet" in the crisis Udall described. More than half a century on, there is a vigorous global conversation about the consequences of industrial growth, and thanks to Udall's vision and the lasting commitment of the USGS and NASA, Landsat is part of it.

Sources

• U.S. Geological Survey, Landsat Brings Understanding to the Impact of Industrialization, Fact Sheet 2016–3054, version 1.1, September 2019. https://doi.org/10.3133/fs20163054
• USGS Earth Resources Observation and Science Center: https://www.usgs.gov/centers/eros
• Words on this page from people and organisations outside the federal government are paraphrased; rewritten in hubnx's own words.