Edward Olsen started his science career as an astronomer looking outward at the universe, but now he has turned his focus in the other direction - inward towards Earth.
A senior member of the technical staff of the Atmospheric Infrared Sounder, he's preparing for the instrument's launch in May aboard the Aqua satellite. The instrument will measure radiances and derive temperature, moisture, ozone and cloud properties in Earth's atmosphere, improving weather prediction and our understanding of Earth's climate system.
Before joining the instrument team, Olsen worked for the Search for Extraterrestrial Intelligence (SETI) project, until JPL's involvement with the program ended in 1993. "It's a bit ironic," says Olsen. "When I was an astronomer trying to observe the sky, water vapor made that difficult. Now, I'm finding it to be interesting in its own right. The global hydrologic cycle is a major driving force of our weather and climate."
Born in Brooklyn, New York, Olsen says he grew up all over. "My father was in the Navy in the war," he says. "I can remember my mother driving cross country at the speed limit--it was 30 miles per hour to save gas. "After getting his undergraduate degree in physics at the Massachusetts Institute of Technology, Olsen went on to complete his graduate work at the California Institute of Technology and the University of Michigan, specializing in radio astronomy.
Q: How is the Atmospheric Infrared Sounder going to improve weather and climate forecasting?
Right now the most detailed measurements of the atmosphere--the basic data that go into computer models that help create forecasts--come from radiosondes, or weather balloons. There are huge gaps in this coverage. Most radiosondes are launched from land, very few over the oceans. There's also little coverage in places like Asia, South America and Antarctica.
The Atmospheric Infrared Sounder is going to observe the entire Earth over a short time span with a 50-kilometer, or about 31-mile, footprint. It will be as if 324,000 radiosondes are daily tunneling up through the air measuring the atmosphere as they go.
Also, radiosondes typically achieve an altitude of 30 kilometers, or about 18 miles. Our instrument will be looking through the entire atmosphere down to the surface, retrieving temperature, water vapor, ozone, cloud top pressures and temperatures, and other gases.
Q: What's your job on the Atmospheric Infrared Sounder?
Right now, I'm preparing for validation. Once the satellite is in stable orbit our instrument's measurements have to be compared to observations from the ground in order to calibrate the instrument properly. Our goal is to provide global soundings of the atmosphere that are as accurate as those of radiosondes or better.
We'll be taking different kinds of looks at the data. One team member is coordinating the validation scientists, who will be conducting a campaign of special observations from Earth in support of our instrument. Another is working with the arrays of automated sea buoys. My responsibility is to statistically compare our instrument's retrievals of temperature and water vapor with the in situ measurements by thousands of radiosondes released daily. I'm building software tools now to analyze that data.
We want to ensure that when the data are publicly released that other scientists, who incorporate it into their weather prediction and climate modeling work, can use it and trust it.
Q: At JPL's open house last year, you fascinated visitors with stories of how weather has affected history. Is this a special interest of yours?
I've been digging a little into Earth's climate history and its impact on our civilization. For the whole of human history, climate has been the invisible hand that has pushed people. It's been move or starve.
For example, there was a reason that Greenland was called "green land." But the climate changed, the weather got colder, and settlements died out. The Barbarian invasion of Europe may have been the consequence of a climate change in eastern Asia that started a chain of westward migrations.
I'm also intrigued by the rapidity with which climate may change. The Greenland ice cores, for example, show signals that temperature changed over a period of decades, so-called "climate flickering." It doesn't take much, a shift in temperature of just a few degrees, to trigger an ice age or a widespread drought.
We live on a knife-edge. We need to know more about our climate system, for it can rapidly change a continent's economy. We better learn what we can do to cope.
Q: What do you do for fun?
I read a lot. Our home is just filled with books. I particularly enjoy science fiction. My wife and I like to go see ballet when we can. I also enjoy traveling in Europe, but have not had the opportunity in quite a while.
We've taken up Regency dancing. A few years ago, we attended a science fiction convention and saw people dancing in the manner you would see in a film about English life in the 18th century. Regency dances can be quite complex. Participants form two lines and then proceed to work through formal patterns in groups of four or six, progressing down the lines and switching roles. Ultimately, everyone has the opportunity to dance with everyone else. It is popular at large science fiction conventions, and there are Regency (and Victorian) dance groups all over the country, including one in Sierra Madre.
Q: What was your first job out of school?
I came to JPL immediately after finishing graduate school and remained ever since. It's been great. I love the work, people and atmosphere. It has been a real privilege to be at JPL during the initial exploration of our solar system.
I've been doing something that I've felt is for the long-term benefit of mankind. It's a dream of mine that millions of years from now, other civilizations in our galaxy will look back upon us with fondness when considering our growth to a mature and accomplished civilization.