Nepedia
Back to Discover
Advanced Reader
🌍

James Hansen

earth science Maturity 9-11 war conflict Next article →

This article covers sensitive topics: war_conflict. Parents can manage visibility in Parental Controls.

James Edward Hansen is a prominent American climatologist.

James Hansen
James Hansen

He is an adjunct professor at Columbia University. There, he directs the Program on Climate Science, Awareness and Solutions. His work focuses on understanding how the Earth's climate changes over time. He also works to connect scientific research to public awareness and policy. Hansen is well known for his research into global warming. He has also become a dedicated climate activist. This advocacy has occasionally led to his arrest during demonstrations.

Hansen began his scientific journey by studying physics and astronomy. He attended the University of Iowa for his undergraduate and graduate studies. He earned a B.A. in physics and mathematics in 1963. He later received an M.S. in astronomy in 1965 and a Ph.D. in physics in 1967. During his education, he was a NASA graduate trainee. He also studied at Kyoto University and the University of Tokyo. In 1967, he started working at the Goddard Institute for Space Studies. This institute is part of the NASA Goddard Space Flight Center.

Early in his career, Hansen focused on planetary atmospheres. He used radiative transfer models to study the planet Venus.

Venus-real color
Venus-real color

These models help scientists understand how energy moves through an atmosphere. At the time, scientists did not know why Venus was so hot. Hansen proposed that aerosols trapped the planet's internal energy. He worked to identify the composition of the Venusian clouds. He and his colleagues used the polarization of sunlight to study the clouds. They discovered the clouds were made of sulfuric acid.

NasaHansenFig1
NasaHansenFig1

This research helped explain the runaway greenhouse effect on Venus. This effect happens when gases trap too much heat, causing temperatures to rise rapidly.

Hansen later applied these models to study the Earth's atmosphere. He wanted to understand how trace gases and aerosols affect our climate. From 1981 to 2013, he directed the NASA Goddard Institute for Space Studies in New York City. He developed global climate models to track temperature trends. One major part of his work involved analyzing surface air temperatures. He used data from meteorological stations around the world.

Peoria ASOS
Peoria ASOS

He analyzed data spanning from the year 1880 to 1985. He found that temperatures in the Northern hemisphere and Southern hemisphere both showed warming. This helped prove that global warming was a widespread phenomenon.

In 1988, Hansen provided famous testimony to the United States Congress.

James Hansen
James Hansen

He stated he was ninety-nine percent certain the Earth was warming. He explained that the greenhouse effect was the cause. He also warned that global warming would increase the likelihood of freak weather. His research showed that the four warmest years on record occurred in the 1980s. Specifically, 1981 and 1987 were the two warmest years at that time. In 1998, his updated data showed the warmest year since instrumental records began in 1880. He noted that the rate of temperature change was faster than ever before.

Hansen has also investigated how specific particles affect the climate. He studied the impact of black carbon on regional weather. Black carbon is dark soot produced by incomplete combustion.

Fire above Snake River
Fire above Snake River

An example of this occurred during the 1988 Yellowstone fires. His research showed that black carbon heats the air. This process increases convection and precipitation. This can lead to larger surface cooling in some areas. He also studied how different greenhouse gases contribute to warming. In 2000, he proposed focusing on non-CO2 gases like methane. He found methane caused significant warming, but carbon dioxide would eventually become the dominant factor.

Today, Hansen continues to advocate for a stable climate system. He uses satellite technology to monitor changes across the entire globe. Satellites are effective because they can observe the whole Earth at once. He also participates in legal efforts to protect the climate. He represented his granddaughter in a lawsuit against the United States government. This case focused on the government's role in protecting a stable climate. His work remains a vital link between complex science and the actions needed to protect future generations.

Hansen 2006 temperature comparison
Hansen 2006 temperature comparison
669 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (8)
File:Venus-real color.jpg
Venus-real color.jpg
File:Peoria ASOS.jpg
Peoria ASOS.jpg
File:Fire above Snake River.jpg
Fire above Snake River.jpg
File:Miamibeachnorth.jpg
Miamibeachnorth.jpg
File:Hansen 2006 temperature comparison.jpg
Hansen 2006 temperature comparison.jpg
File:James Hansen.jpg
James Hansen.jpg
File:NasaHansenFig1.gif
NasaHansenFig1.gif
File:NASA Scientist James Hansen Arrested.jpg
NASA Scientist James Hansen Arrested.jpg
More to explore

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.