1. CSU Sodium Lidar Program: Temperature and winds in the Mesopause Region of the Atmosphere
Joe She and David Krueger, Physics Steve Reising, Electrical and Computer Engineering
50 Miles
Why study the mesopause region?
(80 km = 50 miles above us!)
●Natural occurring Na atoms exist in a layer between 80 and 110 km. Why? What for?
● Up to your imagination – you can use the layer as tracer for probing the upper atmosphere or creating a laser guided star for astronomical observation
● The region supports a counter-intuitive thermal structure (cool summer and warm winter – heavenly)
● Scientists have known of noctiluecent clouds for over 100 years, and have only began to really study them
Question:What we have done and
what are we doing at CSU?
Mesopause
Sodium Lidar Workshop, August, 2006at CSU
Typical temperature profile (K)
Question: When is it coldest in the vicinity of Fort Collins?
Eight-year nighttime temperature measurements over Fort Collins, CO. confirmed the seasonal variation of the mesopause thermal structure.
Summer mean temperature in the polar region is ~130K supporting noctilucent clouds (ice particles
We now have temperature data for 16 years for studies of solar-cycle effects and global (and anthropogenic) change.
Answer: Measuring atmospheric temperatures
and wind speeds in the mesopause region.
Answer: In the summer at 85 km!
Question: Where in Fort Collins can you ‘watch’ wave breaking?
What causes a water wave
to break on a beach?
Does it have anything to do:
with the wave speed?
with nonlinear effects?
Answer: Density waves break in the mesopause region of the atmosphere ...
but there is no beach!
9-day continuous temperature, east and north
winds reveal solar tidal effects (24-hr and
12-hr periods) vividly.
Observing temperature and horizontal wind on 24-hour bases since 2002, correlative study with NASA-TIMED satellite, with details challenge model predictions.
Question: Why we are in ALOMAR, Norway (69oN, 12oE)?
Answer: To observe Cold summer and noctilucent clouds
and Dramatic changes of 45 K within 1 km