Post on 16-Dec-2015
Overview of the Atmospheric Overview of the Atmospheric Radiation Measurement (ARM) Radiation Measurement (ARM) Program’s Mobile Facility (AMF)Program’s Mobile Facility (AMF)
Dave Turner
University of Wisconsin – Madison
COPS Workshop10-11 April 2006Hohenheim, Germany
The Real People The Real People Behind the AMFBehind the AMF
Head Scientist: Mark MillerTeam Members: Mary Jane Bartholomew,
Larry Jones, Kim Nitschke, Doug SistersonChief Engineer: Kevin WidenerProgram Manager: Wanda Ferrell
The ARM Mobile FacilityThe ARM Mobile FacilityInitially Deployed in 2005Initially Deployed in 2005
Pt. Reyes, CaliforniaNiamey, Niger, Africa
CharterCharter Detailed measurements of the cloudy
atmospheric column – in regions of the climate system that are generally
undersampled– in association with the international atmospheric
science community Subset of instruments located at ARM’s fixed
sites– Active and passive sensors– Enhanced surface aerosol system
Deployment duration is 6-12 months
Site Selection ProcessSite Selection Process
International Proposal Competition – ARM Climate Research User Facility
(ACRF) Board selects winning proposal Composed of 40% ARM Scientists and 60%
external scientists Final decision is made by the ARM Program
Manager Proposals rated on scientific merit, facility
leverage, and logistical feasibility
Active and Passive Cloud Active and Passive Cloud Remote SensorsRemote Sensors
3.2-mm Doppler Cloud Radar (WACR)– 30-m vertical resolution– 2-sec temporal resolution– 256 pt. Doppler spectrum at each range gate,
continuously recorded– Polarization– Minimum detectable signal ~ -40 dBZ at 5-km– Sensitivity may exceed –60 dBZ in lowest 1-km– Internal calibration verified by corner reflector
3.2 mm Cloud Radar Doppler 3.2 mm Cloud Radar Doppler Velocity from Niamey, NigerVelocity from Niamey, Niger
“First light”
Active and Passive Cloud Active and Passive Cloud Remote Sensors (cont.)Remote Sensors (cont.)
Vaisala Laser Ceilometer– 905-nm– 15-m, 15-sec resolution– Backscatter profile, cloud base height– Maximum height in cloud free atmosphere: 5.5-km
Micropulse Lidar (MPL)– 523-nm– 30-m, 30-sec resolution– Backscatter Profile, Cloud base height– Maximum height in cloud free atmosphere: 18-km– Cloud optical thickness, aerosol extinction
0000 12000
5
10
15
20
Time (UTC)
Hei
gh
t (k
m)
Biomass Burning
Dust
LIQUID CLOUDS
MPL Example From NiameyMPL Example From Niamey
2400
Bac
ksca
tter
(ar
b u
nit
s)
Active and Passive Cloud Active and Passive Cloud Remote Sensors (cont.)Remote Sensors (cont.)
2-Channel Microwave Radiometer (MWR)– 23.8 and 31.4 GHz– Precipitable water vapor and integrated liquid
water path
12-Channel Microwave Radiometer Profiler– Vertical profiles of water vapor, temperature, and
liquid water content (coarse)– 5 min temporal resolution– 5 frequencies near water vapor resonance
between 22.235 and 30 GHz– 7 frequencies in the band of oxygen resonances
between 51 and 59 GHz
Active and Passive Cloud Active and Passive Cloud Remote Sensors (cont.)Remote Sensors (cont.)
Wind Profiler – 75-m, 6-min resolution– 915 MHz [1270-1400 MHz COPS]– Minimum Height: 120-m– Maximum height: 5.5-km
Atmospheric Emitted Radiance Interferometer (AERI)– 3-19.2 m (1 cm-1 resolution)– 6-min resolution (20-30 sec possible for COPS)– 1.3 degree field-of-view
Surface Shortwave RadiationSurface Shortwave Radiation
Downwelling and Upwelling Total– 0.3-3.0 m global hemispheric irradiance– Unshaded pyranometer
Downwelling Diffuse– 0.3-3.0 m global hemispheric irradiance– shaded pyranometer
Direct-Normal– 0.3-3.0 m– Tracking pyroheliometer with 5.7 degree field-of-
view
Surface Shortwave RadiationSurface Shortwave Radiation Multi-filter rotating shadowband radiometer
(MFRSR)– Total, Diffuse, and Direct-Normal – 6 channels @ 10-nm width
Wavelength (nm) Application
415 aerosol
500 aerosol, ozone
615 aerosol, ozone
673 aerosol, ozone
870 aerosol
940 water vapor
Surface Longwave RadiationSurface Longwave Radiation
Downwelling and upwelling Total– 4.0-50 m global hemispheric irradiance– shaded pyrgeometer
Surface Broadband SummarySurface Broadband SummaryMeasurement Radiometer
ModelUncertainty
Direct Normal Beam NIP ±3.0%
or 4.0 Wm-2
Diffuse Horizontal (sky) PSP ±6.0%
or 20.0 Wm-2
Downwelling Shortwave (global)
PSP ±6.0%
or 10.0 Wm-2
Downwelling Longwave (atmospheric)
PIR ±2.5%
or 4.0 Wm-2
Upwelling Shortwave (Reflected)
PSP ±6.0%
or 15.0 Wm-2
Upwelling Longwave (terrestrial)
PIR ±2.5%
or 4.0 Wm-2
RV Ron BrownCentral Pacific
AOT=0.08
RV Ron BrownSea of JapanAOT=0.98
AMFNiamey, NigerAOT=2.5-3.0
Interesting Sky ImagesInteresting Sky Images
Surface Aerosol SystemSurface Aerosol System Two 3-Wavelength Nephelometers
– 450, 550, 700 nm– One humidified and one dry– Total angular scattering and hemispheric backscattering
coefficients (90º-170º)– Scattering coefficients as a function of RH
Particle Soot Absorption Photometer (PSAP)– Absorption coefficient at 550 nm– Extinction coefficient when combined with nephelometer
measurements Cloud Condensation Nuclei Counter (CCN)
– 7 supersaturation set points ranging from 0.18-1.37– 30-minutes to span range– Measures CN and CCN
How it really looked during
MASRAD
AMF AOSInstruments
denoted AOS AOS
CCN
PNNLSMPS
PNNLCCN
UCDavisSizers
CVIinlet
AOSPSAPCPC
CVIPSAPhygroCPC
CVINeph
UFCN
AO
SN
ephs
BN
L S
MP
SN
AS
A C
aden
zaLi
dar
CVITRAC
AOSTRAC
PNNLAMS
AOSinlet
http://www.cmdl.noaa.gov/gallery/AMF
CVIpumps
AOSpumps
aerosoltrailer
hum
idifi
erUPS
Surface MeteorologySurface Meteorology
Standard variables– T, RH, P, winds (10-m for COPS)– Rainfall (optical rain gauge)– Present Weather
Optical measurement of visibility Fog detection
Latent, sensible, and carbon fluxes– Eddy correlation (2-m height)
New Additions to AMFNew Additions to AMF
CIMEL Sun Photometer – Before COPS
Possibly ARM’s new 90 / 150 GHz microwave radiometer
Data, Data, DataData, Data, Data AMF data are generally available within a day or two
from the ARM data archive (www.archive.arm.gov)– True for all ARM data– Data quality documented afterwards– Reprocessing is occasionally required
Data are open to all investigators Some data streams can be accessed in real-time, if
needed (i.e., radiosonde profiles) Recommendation: talk with Mark Miller and/or the
“instrument mentors” when you start using various ARM datastreams…
ARM tracks data users (# of requests, # of different datastreams, etc.) – this is an important metric