October 13, 2015

OLYMPEX Starts Next Month!

In a few weeks a veritable army of meteorologists will descend upon the Olympic Mountains of Washington State with radars, aircraft, rain gauges, and other meteorological sensors.   All of these resources and participants will be part of the OLYMPEX field program, whose primary goal will be to help NASA evaluate and improve its latest earth-observation satellite:  the GPM satellite, which possesses an advanced downward-looking weather radar.

But Olympex will be much more, with huge suite of observing systems that will probably produce the most comprehensive description of clouds and precipitation over any mountain barrier on the planet.

NASA's recently launched Global Measurement Mission (GPM) satellite is a technological marvel.  Built jointly with Japanese scientists (JAXA), GPM has two powerful weather radars, measuring precipitation below.    The satellite also possesses microwave radiometers that can measure precipitation and cloud properties by the amount of microwave radiation emitted by clouds, raindrops, and ice crystals.   NASA's ambitious goal is to measure precipitation over the entire planet, particularly over the vast areas of the planet with no rain gauges and no weather radars.

But there is one issue:  the new satellite needs to be calibrated and the algorithms that transform radar and microwave radiation into precipitation totals and precipitation type need to be improved and perfected.  To do so requires testbed areas in which precipitation and cloud properties are known with great precision.
And to do so needs massive deployment of weather sensors both on the ground and aloft using both in situ observations and remote sensing (e.g., radars).

That is why OLYMPEX will take place.  Few places on earth have such reliable precipitation and are in an area with a basic weather infrastructure that can be enhanced to secure the required information.

Let me tell you some of the observing assets that will be deployed during OLYMPEX and be prepared to be impressed.

We start with THREE instruments aircraft   An ER-2 that will fly above the Olympics at roughly 60,000 ft, with a range of downward looking sensors.  A DC-8 with more sensors and the ability to launch dropsondes, weather instruments that float downward beneath parachutes.  And finally the low-flying Citation that measures the properties of clouds and precipitation.

Then there will be the surface-based assets (see map below).   In addition, to the current Langley Hill (Hoquiam) and Camano Island (Whidbey Is) radars, 
 additional radars will be added on the coast (NPOL, below), on Vancouver Is. by our Canadian colleagues, and on trucks (below)

Trailers with sophisticated precipitation measuring instruments will be placed up river valleys like the Quinault, and locations such as Hurricane Ridge will be heavily instrumented.

Even low tech snow measuring devices will be used, such as long measuring sticks viewed by automated cams (don't worry, the students don't have to hold the poles all winter!).

Talking about low tech, some of the instruments will be moved into position with mules and on the backs of strong graduate and undergraduate students!

My group and others will use the marvelous OLYMPEX data set to verify our latest computer simulation models:  do they get the precipitation and clouds right?  If not, why not.   And we expect to understand the strengths and weaknesses of the GPM satellite far better by the end of this winter.  Hopefully, this will lead to improvements in our weather forecasting models.

Want to help out?  If you are living in the Chehalis River basin or anywhere on the Olympic Peninsula, why not get a rain gauge and report your observations to the CoCoRahs network

If you would like to learn more, check out the OLYMPEX webpage (http://olympex.atmos.washington.edu/or go to the OLYMPEX facebook page www.facebook.com/OLYMPEX.    

Olympex is led by UW Professor Robert Houze and is mainly funded by NASA. Groups from all over the country will be involved:  UW, NASA, the Jet Propulsion Lab, the National Center for Atmospheric Research, Universities of Oklahoma, Wyoming, and Illinois, the National Parks Service, Environment Canada and more.   If you want a person to contact, the project coordinator is UW scientist Lynn McMurdie (lynnm(at)washington.edu)


  1. Thanks Professor for the plug. I'll be in the Quinault with my gangsta friends helping to get this calibration spot on. We'll be the ones with the rain gear. "The Bunch Field Elk Dodgers." Wish I could be in the front seat of the ER-2. I guess I should have studied harder.

  2. Cliff, I think those are mules,not donkeys.

  3. We need a zoologist on board. Awesome project.

  4. Hi Cliff. I see that Jeff Masters (Weather Underground) is currently addressing our Blob phenomena. I got the idea that you had named it "Blob" (is that actually an acronym?), but he cites your UW colleague Nicholas Bond as the discoverer and namer. Anyway, an interesting piece.

  5. Sorry, I meant to include that Weather Underground link: http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=3154

  6. I just hope they aren't going to leave detritus in the wilderness (like dropsondes). I don't like finding man-made stuff in the wilderness that won't decay like those mylar balloons. I've never found a radiosonde- what happens when they land in a remote area halfway up a Class five face?

    I hope someone knows...

  7. Should have included the Bears helping with snow measurement.

  8. If you are an educator interested in learning more about GPM/OLYMPEX and introducing your students to scientific research, register for tomorrow's free ‪webinar: http://pmm.nasa.gov/OLYMPEX/webinar-registration.

  9. Any chance for some volunteer help on moving the Olympex instruments?

  10. Jessica, that's funny :) Gauges do make good scratching posts (and target practice too!). Hopefully yours survive the winter.

    Sadly I won't be joining you all for this experiment, I switched over to NOAA and am focusing on weather prediction -- we gotta bring GFS into the modern era.



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