3.
Existing Instrument Networks and Individual Sites
The following
instrument networks and individual sites have been identified by the CALIPSO
validation implementation team as being suitable for participating in
validation activities and have been contacted for, or expressed interest in,
participating in the quid pro quo validation program. Each network has a
long history of measurements and a measurement and calibration protocol. For
each network, a brief description of the network is given followed by a list of
pertinent measurements and CALIPSO level II parameters that they validate.
Those parameters with an (*) require assumptions to be calculated that may
reduce their suitability for validation.
Aeronet
is a federation of ground-based remote sensing aerosol networks, largely
sunphotometers, around the world. Aerosol optical thickness at 1020, 870, 670,
500, 440, 380, and 240 nm are derived at most places. Sky radiance measurements
along the solar alumcantar (i.e. at constant elevation angle with varied
azimuth angles) and the solar principal plane (i.e. at constant azimuth angle
with varied scattering angles) are made at 440, 670, 870, and 1020 nm to
retrieve size distribution and phase function. Aerosol optical thickness is
derived every 15 minutes or 0.25 air masses; whichever is more frequent, from
an air mass of 7 in the morning to an air mass of 7 in the evening. Each
measurement consists of a triplet of measurements at each wavelength that are
analyzed for cloud screening and averaged. Sky radiance measurements are taken
6 times a day along the solar alumcantar and 9 times a day along the solar
principal plane. Sun photometers are calibrated by the Langley method every 2-3
months, which is then transferred to field sunphotometers pre- and
post-deployment to an accuracy of 1-2% for aerosol optical thickness, and every
9-12 months to get an accuracy of 5% for sky radiance.
The
following measurements from the Aeronet sites listed in Section 7.1 would be
suitable for CALIPSO validation (validated parameters in parentheses):
Sunphotometer
(ta (532 nm), ta(1064 nm))
3.2
Asian Dust NETwork (AD-Net)
http://www-lidar.nies.go.jp/AsiaNet/
The
AD-Net is an international virtual community, which was formed in February
2001. It was setup to provide rapid communication via the Internet on Asian
dust events. The network observation of Asian dust was originally started in
1997 mainly with lidar groups in Japan. Since 1998, exchange of Asian dust
information with lidar and other surface observations expanded to the East Asia
countries of China and Korea. The AD-Net primary observation campaign take
place every year in northern springtime from March 1 to May 31. Many of the
lidars in the network belong to research programs on the atmospheric radiation
and/or regional air-pollution, and the lidars are operated continuously
throughout year.
Table
II presents a list of instruments, the resolution in time and space of available
lidar, and the CALIPSO Level II parameters validated for each site in the
network.
Table II: List of instruments,
vertical range and resolution, time resolution, and parameters validated for
each station within the AD-Net.
|
Station |
Instrument |
Lidar
range (resolution) |
Lidar time resolution |
Validated parameter |
|
Amami |
0.1-18 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud height/thickness, b'(R,
532nm)‖/b'(R, 532nm)⊥ |
|
|
Beijing |
532 nm w/polarization, 1064 nm lidar. |
0.1-15 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud
height/thickness, b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Chung-Li |
532 nm, 1064 m w/polarization lidar |
1- 30 km (24 m) |
|
aerosol
height/thickness, cloud height/thickness, b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Fukue |
532 nm w/polarization, 1064 nm lidar. |
0.1-15 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud height/thickness, b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Fukuyama |
532 nm w/polarization lidar. |
0-15 km |
15 mins. |
aerosol height/thickness, cloud height/thickness,
b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Hefei |
532 nm w/polarization, 1064 nm lidar. |
0-18 km (30 m) |
15 mins. |
aerosol
height/thickness, cloud height/thickness, b'(R,
532nm)‖/b'(R, 532nm)⊥ |
|
Hohhot |
532 nm w/polarization lidar |
0.1-15 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud
height/thickness, b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Gwangju |
532nm w/polarization, 355,532,1064 nm, 387 nm Raman lidars |
0.5-30 km (7.5 m) |
10 mins. |
aerosol
height/thickness, cloud height/thickness, b'(R, 532nm)‖/b'(R, 532nm), ta(532)*, sa(532)*,ta(1064)*, sa(1064)* |
|
Miyako-jima |
0.1-18 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud height/thickness, b'(R,
532nm)‖/b'(R, 532nm)⊥ |
|
|
Nagasaki |
532 nm w/polarization, 1064 nm lidar |
0.1-18 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud height/thickness, b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
355, 532 w/polarization, 1064 nm, and Raman lidar |
5 mins. |
aerosol height/thickness, cloud height/thickness,
b'(R, 532nm)‖/b'(R, 532nm)⊥ |
||
|
Jeju |
Micro-pulse Lidar |
|
|
aerosol height/thickness, cloud height/thickness |
|
Okayama |
532 nm w/polarization lidar |
0.1-15 km |
15 mins. |
aerosol
height/thickness, cloud height/thickness, b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Sapporo |
532
nm w/polarization, 1064 nm lidar |
0.1-18 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud
height/thickness, b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Seoul |
Micro-pulse
Lidar
|
|
|
aerosol height/thickness, cloud height/thickness |
|
Sri Samrong |
532
nm w/polarization, 1064 nm lidar |
0.1-18 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud
height/thickness, b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Suwon |
532 nm w/polarization, 1064 nm lidar |
0.1-18 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud height/thickness, b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Tokyo |
355nm,
532 nm w/polarization, 1064 nm, 387, 408, 607 nm Raman lidar sun photometer |
0.1-15 km (7.5 m) |
5-10 min. |
aerosol
height/thickness, cloud height/thickness, ta(532)*, sa(532)*,
ta(1064)*, sa(1064)*, Sa (532)*,
Sa (1064)*, Sc(532)*, b'(R,
532nm)‖/b'(R, 532nm)⊥ |
|
Toyama |
532
nm w/polarization, 1064 nm lidar |
0.1-18 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud height/thickness, b'(R, 532nm)‖/b'(R, 532nm) |
|
Tsukuba |
532 nm w/polarization, 1064 nm lidar, 523 nm HSRL |
0.1-15 km (6 m) |
15 mins. |
aerosol
height/thickness, cloud
height/thickness, ta(532),
sa(532), ta(1064)*, sa(1064)*, Sa (532),
Sa (1064)*, Sc(532), b'(R,
532nm)‖/b'(R, 532nm)⊥ |
3.3
Atmospheric Radiation Measurement (ARM)
The
Atmospheric Radiation Measurement (ARM) Program is a multi-laboratory,
interagency program that was created in 1989 with funding from the U.S. Department
of Energy (DOE). The ARM Program is part of DOE's effort to resolve scientific
uncertainties about global climate change with a specific focus on improving
the performance of general circulation models (GCMs) used for climate research
and prediction. These improved models will help scientists better understand
the influences of human activities on the earth's climate. In pursuit of its
goal, the ARM Program establishes and operates field research sites, called
Cloud and Radiation Testbeds (CARTs), in several climatically significant
locations. Scientists collect and analyze data obtained over extended periods
of time from large arrays of instruments to study the effects and interactions
of sunlight, radiant energy, and clouds on temperatures, weather, and climate.
Sites include instruments to measure atmospheric profiles of aerosols and cloud
optical properties, surface eddy flux, and surface meteorology. The instruments
available for CALIPSO validation are discussed below and in Table III.
The following
measurements from the ARM sites would be suitable for CALIPSO validation and
are summarized in Table III (validated parameters in parentheses):
Southern
Great Plains (SGP) Central Facility
Sunphotometer
measurements for 1020 and 499 nm (ta(532nm),
ta(1064nm) and sa(532)*, Sa(532)* from
lidar measurements
Multi-filter rotating shadowband
radiometer for 500 nm (ta(532nm))
Raman Lidar (runs day/night with
39 m range resolution) with 355 nm depolarization channel and a 387 nm Raman
channel (b'(R, 532nm)
‖/b'(R, 532nm)⊥*, aerosol height/thickness,
cloud height/thickness)
Ceilometer measurements at 905 nm
(aerosol height/thickness, cloud height/thickness)
Micro-pulse lidar at 523 nm
(aerosol height/thickness, cloud height/thickness)
mm-Wavelength cloud radar (cloud
height/thickness)*
The following
instruments are also present but do not directly validate any CALIPSO parameters:
condensation nuclei counter, optical particle counter (31 channels between
0.1-10 mm and
one greater than 10 mm),
ozone monitor, microwave radiometer (31.4 GHz), atmospheric emitted radiance
interferometer (3-20 mm or
500-3300 cm-1, resolution 1 cm-1), radiosondes, 50 and
915 MHz Radar wind profiler/RASS, camera centered on zenith, whole sky imager
(450 and 650 nm), narrow field of view sensor (869 nm, centered on zenith),
absolute solar transmittance interferometer (1-5 mm or 2000-10000 cm-1, resolution 2 cm-1,
pyranometer, pyrgeometer, pyrheliometer, uv-b radiometer, solar radiance transmission
interferometer (620-1350, 1500-2050, 2020-2550, 2420-3080, 3010-3830, 4020-4300
cm-1, 3 times a day), shortwave spectrometer, uv spectroradiometer,
surface meteorological observing system (1 minute wind speed and direction,
temperature, relative humidity, pressure, rain amount), temperature and humidity
at 25 and 60 m, and a chilled mirror.
Southern Great Plains (SGP)
Extended Facilities (sites listed in Section 7.1)
Multi-filter rotating shadowband
radiometer for 500 nm (ta(532nm))
Also, a surface meteorological observing
system (1 minute wind speed and direction, temperature, relative humidity,
pressure, rain amount) is present.
Tropical Western Pacific (TWP) (Manus island, Nauru island, and
Darwin)
Ceilometer at 905 nm (aerosol
height/thickness, cloud height/thickness)
Micropulse lidar at 523 nm
(aerosol height/thickness, cloud height/thickness)
mm-Wavelength cloud radar (cloud
height/thickness)*
Sunphotometer for 1020 and 499 nm
(ta(532nm), ta(1064nm), and sa(532)*, Sa(532)* with
the lidar)
Multi-filter rotating shadowband
radiometer for 500 nm (ta(532nm))
The following
instruments are also present but do not directly validate any CALIPSO parameters:
microwave radiometer (31.4 GHz), atmospheric emitted radiance interferometer
(3-20 mm or
500-3300 cm-1, resolution 1 cm-1), radiosondes, 915
MHz Radar wind profiler/RASS, whole sky imager (450 and 650 nm), absolute
solar transmittance interferometer (1-5 mm or 2000-10000 cm-1, resolution 2 cm-1),
pyranometer, pyrgeometer, pyrheliometer, uv-b radiometer, solar radiance transmission
interferometer (620-1350, 1500-2050, 2020-2550, 2420-3080, 3010-3830, 4020-4300
cm-1, 3 times a day), surface meteorological observing system (1
minute wind speed and direction, temperature, relative humidity, pressure,
rain rate).
North Slope of Alaska (Barrow)
High spectral resolution lidar
(HSRL) (100 m to 37.5 km with day/night operation) 532
nm w/depolarization and 1064 nm
(aerosol height/thickness, cloud height/thickness, ta(532), sa(532), ta(1064), sa(1064)*, Sa (532), Sa
(1064)*, tc(532), sc(532), Sc (532), b'(R, 532nm)‖/b'(R, 532nm)⊥)
Ceilometer at 905 nm (aerosol
height/thickness, cloud height thickness)
Micropulse lidar at 523 nm
(aerosol height/thickness, cloud height/thickness)
mm-Wavelength cloud radar (cloud height/thickness)
*
Sunphotometer for 1020 and 499 nm
(ta(532nm), ta(1064nm), and sa(532)*, Sa(532)* with
the lidar)
Multi-filter rotating shadowband
radiometer for 500 nm ((ta(532nm))
The
following instruments are also present but do not directly validate any CALIPSO
parameters: microwave radiometer (31.4 GHz), atmospheric emitted radiance
interferometer (3-20 mm or
500-3300 cm-1, resolution 1 cm-1), radiosondes, 915 MHz
Radar wind profiler/RASS, whole sky imager (450 and 650 nm), absolute solar
transmittance interferometer (1-5 mm or 2000-10000 cm-1, resolution 2 cm-1),
pyranometer, pyrgeometer, pyrheliometer, uv-b radiometer, solar radiance
transmission interferometer (620-1350, 1500-2050, 2020-2550, 2420-3080,
3010-3830, 4020-4300 cm-1, 3 times a day), wind speed and direction,
temperature, relative humidity at 2, 10, 20, and 40 m and pressure, visibility,
and precipitation at the ground.
North Slope of Alaska (Atqasuk)
Multi-filter rotating shadowband
radiometer for 500 nm ((ta(532nm))
Table III: Summary of instruments
describe above at the various ARM sites.
|
|
Southern Great Plains Central Facility |
Southern Great Plains Extended Facilities |
Tropical Western Pacific |
North Slope of Alaska (Barrow) |
North Slope of Alaska (Atqasuk) |
|
Sun Photometer |
1020 and 499 nm |
|
1020 and 499 nm |
1020 and 499 nm |
|
|
MFRSR |
500 nm |
500 nm |
500 nm |
500 nm |
500 nm |
|
Raman Lidar |
355 nm with polarization and 387 nm, both with 39 m vertical resolution |
|
|
|
|
|
Ceilometer |
905 nm |
|
905 nm |
905 nm |
|
|
Micro-pulse Lidar |
523 nm |
|
523 nm |
523 nm |
|
|
HSRL |
|
|
|
532 nm with polarization, 1064 nm, both with 100 m vertical resolution and range to 37.5 km |
|
|
Mm wavelength cloud radar |
Yes |
No |
Yes |
Yes |
No |
|
Other instruments not directly related to validation |
Yes (see text) |
Yes (see text) |
Yes (see text) |
Yes (see text) |
No |
3.4
Baseline Surface Radiation Network (BSRN)
BSRN is
a project of the World Climate Research Programme (WCRP) aimed at detecting
important changes in the earth's radiation field, which may cause climate
changes. The objective of the BSRN is to provide, using a high sampling rate,
observations of the best possible quality, for short and longwave surface
radiation fluxes. These readings are taken from a small number of selected
stations, in contrasting climatic zones, together with collocated surface and
upper air meteorological data and other supporting observations.
The
following measurements from the BSRN sites listed in Section 7.1 would be
suitable for CALIPSO validation (validated parameters in parentheses):
Sunphotometer (ta (532 nm), ta(1064 nm))
Also all
stations measure global, direct, and diffuse broadband solar radiation while
most stations measure downward longwave, temperature, relative humidity, and
pressure. Payerne, Von Neumayer, and Boulder measure upward shortwave and
longwave irradiance and have radiosondes. Toravere and Tateno measure upward
shortwave and longwave irradiance.
3.5
Climate Monitoring and Diagnostics Laboratory (CMDL)
http://www.cmdl.noaa.gov/aerosol/
The
CMDL of the National Oceanic and Atmospheric Administration (NOAA) conducts
research related to the atmospheric constituents that are capable of forcing
change in the climate of the earth or may deplete the ozone layer. Aerosol
measurements began at the CMDL baseline observatories in the mid-1970s as part
of the Geophysical Monitoring for Climate Change. The goal of this
regional-scale monitoring program is to characterize means, variability, and
trends of climate-forcing properties of different types of aerosols, and to
understand the factors that control these properties.
The
following measurements from the CMDL sites listed in Section 7.1 would be
suitable for CALIPSO validation (validated parameters in parentheses):
Sunphotometer (ta (532 nm), ta(1064 nm))
The
site at Kosan has a 4-channel sun photometer, 3 spectral pyranometers, 2
pyrheliometers, an MFRSR, and instruments for measuring surface pressure,
temperature, and humidity. Also at Kosan, chemical ion analysis and total
gravimetric mass is analyzed once a week on particles collected on the
absorption photometer filters.
http://lidarb.dkrz.de/earlinet/index.html
EARLINET’s
objective is to establish a quantitative comprehensive statistical database of
the horizontal, vertical, and temporal distribution of aerosols on a
continental scale. The goal is to provide aerosol data with unbiased sampling,
for important selected processes, and air-mass history, together with
comprehensive analyses of these data. The objectives will be reached by
implementing a network of 21 stations distributed over most of Europe, using
advanced quantitative laser remote sensing to directly measure the vertical
distribution of aerosols, supported by a suite of more conventional
observations. Special care will be taken to assure data quality, including
intercomparisons at instrument and evaluation levels.
Table
IV presents a list of instruments, the resolution in time and space of any
available lidar, and the CALIPSO Level II parameters validated for each site in
the network.
Table IV: List of instruments,
vertical range and resolution, time resolution, and parameters validated for
each station within the EARLINET.
|
Station |
Instrument |
Lidar
range (resolution) |
Lidar time resolution |
Validated parameter |
|
Aberystwyth |
387 nm Raman lidar, wind profiler |
0.5-8 km (30 m) |
5.5 mins. |
aerosol height/thickness, cloud height/thickness, ta(532)*, sa(532)*, ta(1064)*, sa(1064)*, tc(532)*, sc(532)* |
|
Athens |
532 nm lidar, meteorological data (P,T,U) |
0.5-5 km (7.5-15 m) |
6 mins. |
aerosol
height/thickness, cloud height/thickness |
|
Barcelona |
1064 nm lidar, aerosol spectrometer, pyranometer |
0.25-10 km (7.5 m) |
1 min. |
aerosol height/thickness, cloud height/thickness |
|
Cabauw |
355 nm and 532 nm Raman lidar w/depol and 1064 nm backscatter lidar (other instrumentation similar to ARM SGP site |
1-15 km |
30 min. |
aerosol
height/thickness, cloud height/thickness, ta(532),
sa(532), ta(1064)*, sa(1064)*, Sa (532),
Sa (1064)*, tc(532),
sc(532), Sc
(532), b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Garmisch |
532 nm, 1064 nm lidar, visibility meter, pyranometer |
0.2-10 km (15 m) |
0.5 min. |
aerosol height/thickness, cloud height/thickness |
|
Hamburg |
387 nm Raman lidar, and AERONET sunphotometer, ceilometer |
0.3-9 km (15 m) |
10 s |
aerosol
height/thickness, cloud height/thickness, ta(532),
sa(532)*, ta(1064), sa(1064)*
|
|
Jungfraujoch |
532 nm w/polarization, 1064 nm, 387 Raman lidars, sunphotometer |
4-11 km (7.5 m) |
100 s |
aerosol height/thickness, cloud height/thickness,
ta(532), sa(532)*, ta(1064), sa(1064)*, Sa (532)*,
Sa (1064)*, tc(532)*,
sc(532)*, Sc(532)*,
b'(R, 532nm)‖/b'(R, 532nm)⊥ |
|
Kuhlungsborn, Germany |
532, 1064 nm, and 386, 607.4 nm Raman lidars, and 529.1, 530.2, 532.1 nm detection, radiosondes, ozone lidar, 2 dye lasers, 1 alexandrite laser |
1-12 km, 10-35 km (50 m) |
8, 33, 133 s |
aerosol height/thickness, cloud height/thickness, ta(532), sa(532), ta(1064)*, sa(1064)*, Sa (532), Sa (1064)*, tc(532), sc(532), Sc (532) |
|
L'Aquila, Italy |
382 nm Raman lidar, SODAR, radiosonde |
1-12 km (300 m) |
5 mins. |
aerosol height/thickness, cloud height/thickness, ta(532)*, sa(532)*, ta(1064)*, sa(1064)* |
|
Leece, Italy |
382 nm Raman lidar, sunphotometer |
0.4 - 7 km (1.5 m) |
3 mins. |
aerosol height/thickness, cloud height/thickness, ta(532), ta(1064) |
|
Leipzig |
532 nm w/polarization, 1064 nm, and 387, 408, 529, 530.2, 533.7, 535, 607 nm Raman lidar, sun photometer, radiosonde |
0.5 km - trop. for extinction and 0.1 - trop. for backscatter (60 m) |
30 s |
aerosol
height/thickness, cloud height/thickness, ta(532),
sa(532), ta(1064), sa(1064)*, Sa (532),
Sa (1064)*, tc(532),
sc(532), Sc
(532), b'(R, 532nm)‖/b'(R, 532nm)⊥
|
|
Lisbon |
532 nm, 1064 nm lidar |
0.3-5 km (1.5 m) |
1 s |
aerosol height/thickness, cloud height/thickness |
|
Linkoping |
355 nm lidar, pyranometer |
0.1-10 km (7.5 m) |
0.1-300s, usu. 300 s |