Pathfinder Atmospheres
Extended
Andrew Heidinger, Mike Foster and Andi Walther
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A satellite cloud data set from NOAA/NESDIS with a lot
of CIMSS contributions.
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Mainly funded to be an AVHRR data set which spans
1978 to 2013+.
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Experimental data available now from GOES and
MODIS
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Plans to continue PATMOS-x on VIIRS
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Part of the GEWEX Cloud Assessment and a project
within the WMO SCOPE-CM.
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Only one of multiple cloud climate data sets in CIMSS.
ž AVHRR
is the Advanced Very High
Resolution Imager and it flies on the
NOAA POES satellites and more recently
on the METOP satellites.
ž AVHRR spans 1978 to 2025(?)
ž 5 generally well calibrate-able channels
(0.63, 0.86, 1.6 / 3.75, 11 and 12 µm)
ž Global record has 4 km resolution though
1 km is available regionally from the
onset.
First Cordless Phones
TIROS-N
A 10-bit AVHRR sensor with 4 channels and 4 km Global Resolution
Samsung Galaxy S3
NOAA-19
A 10-bit AVHRR sensor with 5 channels and 4 km Global Resolution
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It is the longest (w/ HIRS) continues consistent satellite record.
It’s record is big enough (30Tb) that is was a challenge to
reprocess until recently.
It has turned to be a pretty good radiometer with calibrations that
are improving in time.
It does offer skill in surface temperature, vegetation, clouds,
aerosols and fires so it is quite a important source of data.
Plus, it’s a NOAA/NESDIS data source so we own it.
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1990-1997: PATMOS was part of the NASA/NOAA Pathfinder Program which
was a preparatory exercise for the EOS (e.g. MODIS) era. Was a $1,000,000
project and allowed for one pass through the data.
2002: PATMOS-x derived from new AVHRR Operational Processing system
(CLAVR-x)
2004-2006: ORA funded PATMOS-x as one of its ORA Climate Pilot Project.
This funded the copy of the SAA/CLASS Level-1b archive on tape to disks at
NESDIS and then CIMSS.
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2009-2010: NCDC funded PATMOS-x to make the first recalibration of the
solar channels for every AVHRR sensor (including morning satellites).
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2011-2013: NCDC funded PATMOS-x to deliver FCDRs 1978-2009. FCDRs
are calibrated reflectances
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2013: NCDC funded delivery of 2010-2012 and begin monthly updates.
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2014+: NCDC funds TCDRs (cloud products) and creation of new HIRS
+AVHRR CDRs. (builds off Paul Menzel’s NCDC project).
ž  PATMOS-x
taps into the GOES-R AWG
algorithms and we run one algorithm on all
sensors. ( a key CIMSS linkage)
ž  We try to stay current with ancillary data (CFSR
0.5o, OISST v2, MODIS surface reflectances, …)
ž  PFAAST
ž  Other
is still our IR model of choice.
algorithms (solar insolation, NDVI, SST,
aerosol) come from NESDIS operations.
ž Pollution
impacts on clouds in the East
China Sea (Bennartz et al)
ž Oceanic productivity
ž Long-term trends in Cloudiness (Level-3
type analysis)
ž Long-term Aerosol Climate Studies
ž Land Surface Temperature over USA
ž Insolation variability studies.
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Our goal is to allow people to make their own products or filter
ours in ways we did not think of.
We include all of the calibrated reflectances and brightness
temperatures.
We also include some useful metrics like 3x3 standard deviations.
Selected ancillary data like surface type, elevation, emissivity,
reflectance and temperature.
Some fields like clear-sky brightness temperatures that help
diagnose regions of NWP+RTM failure
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Standard cloud products and their uncertainty
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Select products from NESDIS (aerosol, OLR, surface temperature)
Cloud
Ancillary +
Non-Cloud
Observations
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have never had the resources to archive
a full resolution product (Level-2)
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also realized that no Level-3 product was
ever good enough to make most people
happy most of the time. (especially Claudia
Stubenrauch in the GEWEX Cloud
Assessment)
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by necessity, we decided to make
“Level-2b” data (which we probably should
have called Level-2g).
Level-2b Employs
Nearest Neighbor
Sampling on a
Equal-Angle Grid
level-2 grid
Level-2b grid
Level-2b point
Nearest Level-2
point
Max error in geolocation = ½ level-2
resolution
Level-2b throws a lot of the data but
keeps a lot of the flexibility
X
X
Level-2b AVHRR 0.1 degree
Simultaneous Nadir Overpass
between AVHRR and MODIS
Level-2b for calibration
A 1x1 degree Level-3 Monthly Mean
for GEWEX
Arbitrary n-dimensional histograms
(here Pc vs τ like ISCCP)
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Another benefit of the Level-2b is that it preserves the relative pixel
positions.
This allows one to do image processing like storm centric analysis or
object tracking.
The example below shows a hurricane tracked by the CFSR surface
pressure and some objects showing main central ice mass (light grey)
and regions with convection hitting the Tropopause (white).
Data missing in archive
Orbital drift is a blessing and a curse. Our observation times vary but we
do see all points of the earth at every hour of the day.
january
Foster, M. J. and A. K. Heidinger,
2012: PATMOS-x: Results from a
Diurnally Corrected Thirty-Year
Satellite Cloud Climatology. J.
Climate, 26, 414–425. doi: http://
dx.doi.org/10.1175/JCLID-11-00666.1
june
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NCDC is the official source of
the PATMOS-x AVHRR data.
We do try and maintain access
to some data here at CIMSS to
whet people’s appetites.
We have ftp access and perl
script to automate the process.
Our goal is functionality.
CIMSS is working on a new
multi-project portal.
ž  The
PATMOS-x project has critical contributions
from Amato Evan, Mike Foster, Aleksandar Jelenak,
Christine Molling, Mike Pavolonis, William Straka
and Andi Walther.
ž  The
PEATE made our 2010 NCDC delivery
possible.
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Zara cluster is now cortical too.
ž  PATMOS-x
foundation
builds on the NOAA/NESDIS ORA
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We do need better interfaces for people to grab our climate data.
Climate community is mainly small research groups with specific
questions
NCDC is funding us to make AVHRR+HIRS records which will also
us to make MODISish data from 1980 on. Could also do the same
for CrIs+VIIRS, GOES-Sounder and ABI Base channels could be:
(0.65, 3.8, 6.7, 8.5, 11,12, 13.3 µm)
There is much more European activity in this area than American,
we need to partner with them but also focus on areas where we
can be leaders.
diurnal maxima (local time) with amplitude
0.10
cloud anomaly
0.05
0.00
-0.05
-0.10
1985
1990
1995
2000
2005
2010
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PATMOS-x has collaborated
much with the EUMETSAT CMSAF (SMHI,KNMI, and DWD)
PATMOS-x partners with the
CM-SAF on a WMO SCOPE-CM
Project
PATMOS-x was a participant in
the GEWEX Cloud Assessment
Some PATMOS-x data appeared
in the EUMETSAT CREWs.
0.10
total cloud - land
n* = 66.7
A
patmos-x (corrected)
uncorrected
0.05
0.00
n* = 33.4
D
patmos-x (corrected)
uncorrected
0.05
-0.05
0.15±0.16%/decade
-0.28±0.21%/decade
-0.10
-0.50±0.18%/decade
-0.96±0.22%/decade
-0.10
1985
1990
1995
water cloud - land
2000
2005
n* = 31.0
B
1985
0.10
0.05
0.05
0.00
0.00
-0.05
1990
1995
water cloud - ocean
2000
2005
n* = 28.8
E
-0.05
-0.76±0.25%/decade
-1.09±0.36%/decade
-0.10
-0.99±0.29%/decade
-0.90±0.26%/decade
-0.10
1985
0.10
total cloud - ocean
0.00
-0.05
0.10
0.10
1990
1995
ice cloud - land
2000
2005
n* = 22.8
C
1985
0.10
0.05
0.05
0.00
0.00
-0.05
1990
1995
ice cloud - ocean
2000
2005
n* = 25.0
F
-0.05
0.96±0.20%/decade
0.82±0.19%/decade
-0.10
0.59±0.14%/decade
0.03±0.10%/decade
-0.10
1985
1990
1995
2000
2005
1985
1990
1995
2000
2005