JOINT BASE LEWIS-McCHORD, Wash. — The weather forecast for the Olympic Peninsula is dark and rainy, and that’s putting the scientists behind NASA’s OLYMPEX campaign in a sunny mood.
“The really exciting thing that everyone’s talking about is, there’s this huge rain event that’s coming in,” says Rachael Kroodsma, an atmospheric scientist from NASA’s Goddard Space Flight Center, helping to get a specially outfitted DC-8 plane ready to fly into the storm this week. “There’s a lot of buzz about that. … It’s a good start to the campaign.”
Usually, bad weather is bad news.
Not for OLYMPEX, the Olympic Mountain Experiment.
Under the leadership of NASA and the University of Washington, the months-long effort is using aerial observations as well as a bevy of radars and rain gauges to validate orbital data from the Global Precipitation Measurement satellite, also known as GPM. The $3 million campaign is the latest of several field studies aimed at making sure the satellite readings reflect ground truth.
“You don’t want to be off by a factor of two or three,” said UW atmospheric scientist Lynn McMurdie, project manager and principal investigator for OLYMPEX.
The results should lead to better computer models for predicting wet weather as well as its effects – including dangerous landslides like the one near Oso that caused 43 deaths last year.
The improvements in precipitation prediction can have benefits far beyond western Washington. For example, the National Weather Service has issued a flood watch for the Olympics this weekend, based on extensive satellite and radar data. It’d be great to use satellites to extend the same kind of predictability to parts of the world that aren’t as well covered.
“Researchers around the world are able to take the satellite information and get a better picture of wher we might have extremes – floods or landslides on one hand, or drought on the other hand,” Dalia Kirschbaum, a researcher at Goddard who specializes in landslide hazard assessment, told GeekWire. She said the information could help farmers plan their crops better, help epidemiologists anticipate malaria outbreaks, or even help scientists predict zebra migrations.
Although GPM can provide unprecedented global data about precipitation, the algorithms that translate its readings into forecasts have to be tweaked to reflect a wide variety of real-world rainfall conditions. That’s why NASA needs field campaigns such as OLYMPEX.
Why did NASA pick the Olympic Peninsula as a hot spot for algorithm tweaking? No one who lives here needs to ask.
The region holds the record for precipitation in the Lower 48 states, with some places registering average annual rainfall of more than 180 inches. As clouds sweep eastward from the Pacific Ocean, they hit the Olympic Mountains’ dramatic 7,000-foot gain in elevation – which serves as the ideal rainmaker, and therefore the ideal laboratory for validating GPM’s data.
The modified Douglas DC-8 research jet at McChord carries the same kinds of radar and microwave instruments that GPM is carrying. Starting today, it’s double-checking the satellite data from a height of 39,000 feet, with an assist from a small Cessna Citation jet that can fly right through low-elevation clouds.
— NASA Social (@NASASocial) November 12, 2015
— Steve Nesbitt (@70_dbz) November 12, 2015
A civilian version of the Lockheed U-2 spy plane, known as the ER-2, will take on similar validation tasks starting next week at altitudes ranging up to 65,000 feet.
The kind of flying that will be required for OLYMPEX turns traditional aviation wisdom on its head. “I was told, never mess with an anvil top,” said Chris Jennison, a program manager at NASA’s Armstrong Flight Research Center in California, where the high-flying planes are based. “Well, we mess with anvil tops all the time.”
On Wednesday, Jennison and other OLYMPEX team members gave briefings about the campaign to three dozen Twitter users at UW and Joint Base Lewis-McChord under the auspices of the space agency’s @NASASocial program. The social sessions continued today with tours of OLYMPEX’s ground-based assets on the Olympic Peninsula.
The on-the-ground efforts are just as daunting as the airplane flights, in part because some of the places OLYMPEX’s scientists want to monitor are incredibly remote.
Scores of rain gauges have been set up across the peninsula. Some of the equipment had to be carried 15 miles into the wilderness of Olympic National Park on the backs of mules. A 30-foot-wide radar dish has been installed on the coast, near Taholah on the Quinault Indian Reservation. Meanwhile, a Colorado-based team is operating a “Doppler On Wheels” dish off the back of a truck.
For OLYMPEX’s scientists, pilots and technicians, the toughest challenge may well be weathering the darkest time of the year in one of the rainiest parts of the country. Seasonally affective disorder can be an occupational hazard. But as the OLYMPEX campaign gets under way, the team says it’s up to the challenge.
“Yeah, there’s a lot of rain,” said the University of North Dakota’s Mike Delaney, an instrumentation engineer for the DC-8. “So that’s exciting.”