That New York Times headline summarized testimony presented to the U.S. Congress 34 years ago, on 23 June 1988.
James Hansen, director of the NASA Goddard Institute for Space Studies, told the U.S. Senate Energy and Natural Resources Committee that “the earth is warmer in 1988 than at any time in the history of instrumental measurements.”
A major report from the World Meteorological Organization and the United Nations Environment Program earlier this month concluded that without a major effort to fight warming, global temperatures could increase by 0.54 degrees Fahrenheit per decade until the middle of the next century, and sea levels could rise by a foot.
What has happened since that testimony 34 years ago, other than we now know that warming is only one part of climate change?
Congress listened with enough attention to join the global community in banning refrigerant gases. The 1987 Montreal Protocol, an international treaty, banned chlorofluorocarbons. In 1990, Congress amended, and President George H.W. Bush signed, the Clean Air Act “to require manufacturers to replace substances that deplete stratospheric ozone with non-ozone-depleting substances.”
On 01 January 2020, 30 years later, a ban on freon took effect.
The year 1988 would be the hottest (57.61º) in the 130 years that global temperature records had been maintained. The two previous hottest years on record were 1987 (57.59º) and 1983 (57.56º). The six warmest years on record at that time were 1988, 1987, 1983, 1981, 1980 and 1986.
According to data from more than 1,000 weather stations. the average year-round air temperature in 1988 was 0.61º greater than the average for the period 1950-79 (57º).
Since the 1980s, each decade has been warmer than the prior one. In 2020, Earth’s global average surface temperature tied with 2016 as the warmest year on record, according NASA.
“The last seven years have been the warmest seven years on record, typifying the ongoing and dramatic warming trend,” said GISS Director Gavin Schmidt. “Whether one year is a record or not is not really that important – the important things are long-term trends. With these trends, and as the human impact on the climate increases, we have to expect that records will continue to be broken.”
Since the 1800s, human activity such as burning fossil fuels has been the main driver of climate change. An early documented danger sign came in the 1950s, when Charles David Keeling recorded an increase in atmospheric carbon dioxide at the Mauna Loa Observatory in Hawaii.