The meteorological variables in this data set are surface air pressure, air temperature, dew point temperature, wind speed, wind direction, precipitation, incoming solar (shortwave) radiation, and incoming infrared (longwave) radiation.
Note that some of the data files have been compressed using Zip compression. See Section 8.2 for details.
Wood, E., and V. Pauwels. 2001. BOREAS Follow-On HMet-02 Area and Regional Hourly Gridded Met[eorological] Data, 1994-1996. Available on-line [http://www.daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A.
1.2 Data Set Introduction
BOREAS Hydromet/Carbon Model Subgroups
meteorological forcing data sets for Phases I, II, & III modeling intercomparisons.
1.3 Objective/Purpose
Surface station data and remote sensing
data over the BOREAS region were gridded in order to provide the investigators
of the BOREAS Follow-On Water/Energy modeling subgroup with a standard
model forcing data set for intercomparison studies. Six (6) different hydrometeorological
models & nine (9) different carbon models were selected for intercomparison
purposes.
1.4 Summary of Parameters
Meteorological forcing data consist
of following eight (8) parameters: 1) Air temperature 2) Dew point temperature
3) Wind speed 4) Wind direction 5) Air pressure 6) Incoming solar radiation
7) Incoming long wave radiation 8) Precipitation
1.5 Discussion
This data set includes Phases 2 and
3 of the three categories of meteorological forcing data sets that have
been assembled for the BOREAS Hydrometeorological and Carbon Assimilation
Model Intercomparison Projects as part of the BOREAS Follow-on activities.
The first phase of the meteorological forcing data sets, Phase I data,
at point/tower scale, has also been produced.
1.6 Related Data Sets
BOREAS AES MARSII Surface Meteorological Data
BOREAS AES READAC Surface Meteorological Data
BOREAS AFM-07 SRC Surface Meteorological and Radiation Data
BOREAS TF-1 SSA-OA Tower Flux, Meteorological, and Soil Temperature
Data
BOREAS TF-2 SSA-OA Tower Flux, Meteorological, and Precipitation Data
BOREAS TF-3 NSA-OBS Tower Flux, Meteorological, and Soil Temperature
Data
BOREAS TF-4 SSA-YJP Tower Flux, Meteorological, and Canopy Condition
Data
BOREAS TF-6 SSA-YA Surface Energy Flux and Meteorological Data
BOREAS TF-8 NSA-OJP Tower Flux, Meteorological, and Soil Temperature
Data
BOREAS TF-9 SSA-OBS Tower Flux, Meteorological, and Soil Temperature
Data
BOREAS TF-10 NSA-Fen Tower Flux and Meteorological Data
BOREAS TF-10 NSA-YJP Tower Flux, Meteorological, and Porometry Data
BOREAS TF-11 SSA-Fen Tower Flux and Meteorological Data
BOREAS TGB-4 NSA-BVP Tower Flux and Meteorological Data
BOREAS RSS-14 Level-2 GOES-7 Shortwave and Longwave Radiation Images
BOREAS Follow-on HMet-02 Area and Regional Hourly Gridded Met. Data,
1994-1996
2.2 Title of Investigation
A terrestrial water and energy budget
for the BOREAS study region scale using field measurements, remote sensing,
and modeling.
2.3 Contact Information
Contact 1:
Valentijn Pauwels
Ghent University
Ghent, Belgium
Tel. + 32 - 9 - 264 61 37
Fax + 32 - 9 - 264 62 36
email: vpauwels@taoren.rug.ac.be
Contact 2:
Prof. Eric Wood
Princeton University
Princeton, NJ
Tel. (609) 258-4675
Fax. (609) 258-2799
email : efwood@Princeton.edu
(2) Special Issue on Remote Sensing in BOREAS in 1997 Canadian Journal of Remote Sensing (vol 23/no 2).
(3) 2nd BOREAS Special Issue in 1999 Journal of Geophysical Research (vol 104/issue D22).
AES Continuous Recording Stations: 15 min
These stations are long-term meteorological
sites which record continuous observations at 15 minute interval. Standard
suite of meteorological variables is measured including pressure, temperature,
humidity, wind speed, and wind direction. SW and LW radiation fluxes are
not measured. Fourteen (14) Automatic Meteorological Station (AMS)-type
systems collected data from August '93 through December '96. Six (6) Meteorological
Automatic Reporting System II (MARS-II) stations and one Remote Environmental
Automatic Acquisition Concept (READAC) station collected data during 1994
IFCs only. All of these stations collected standard meteorological data
and no radiation data.
SRC Meteorological Stations Suite A & B
These stations were installed and operated
by SRC specially for BOREAS project and recorded observations at a 15 minute
interval. This data set provides most complete coverage (temporally and
spatially) of meteorological conditions in Southern and Northern Study
Areas during period 1994-1996. Unlike most flux towers, these stations
also operated during winter months. Stations recorded full suite of meteorological
measurements, although only subset (Suite B) measured LW radiation fluxes.
Flux Tower Sites: 15 min
Largest suites of variables were measured
at BOREAS flux tower sites. Most towers measured all standard meteorological
variables at different levels. All levels are retained in quality controlled
BORIS data sets. Few towers operated during entire period from 1994-1996.
HYD-09 Belfort and Tipping Bucket Rain Gauges
HYD-09 Science Team operated dense precipitation
gauge network in Northern and Southern Study Areas during much of BOREAS
field period, although most observations were obtained during summer months
of 1994 and 1996.
Canadian Forest Service Meteorological Stations
These stations recorded hourly observations
during summers of 1994 and 1995 obtaining temperature, humidity, wind speed,
wind direction, and precipitation.
Canadian Historical Stations: Daily
These stations, also operated by AES
Canada, only record daily minimum, maximum, and mean temperature and precipitation.
Canadian Historical Stations: Hourly
These stations, also operated by AES
Canada, record observations on an hourly basis, involving larger suite
of variables than measured by daily stations, including pressure, temperature,
humidity, wind speed, wind direction, and cloudiness. SW and LW radiation
fluxes are not measured.
During winter months, when precipitation
estimates by each of the previously listed stations were missing, daily
precipitation data were resampled into hourly estimates using the average
diurnal cycle of precipitation, and then during December, January, and
February, these precipitation data were gridded.
Remote sensing data from following sources were also used in the gridding:
GOES satellite retrievals (Gu & Smith SRB algorithm):
Retrievals of incoming solar radiation
over The BOREAS region, from days 36-263 (Feb 5-Sep 20)-1994 and days 43-296
(Feb 12-Oct 22)-1996, were blended into gridded data sets -- treating each
GOES pixel as a separate station.
Enterprise WSR-100 radar:
Retrievals of precipitation over Southern
Study Area, from days 132-266 (May 12-September 23)-1994, were blended
into gridded data sets -- treating each radar pixel as a separate station.
In order to eliminate drizzle originating
from the interpolation of rainfall over large distances, all precipitation
values of intensity lower than 0.25 mm hr-1 have been set to zero.
7.1.1 Spatial Coverage
The grid chosen by the Water/Energy modeling subgroup was used for this data set.For Phase II NSA data set, grid corner locations are (UTM zone 14)
Corner Northing (UTM) Easting (UTM) ------------------------------------------------------ NW 6202000 514000 NE 6202000 548000 SW 6170000 514000 SE 6170000 548000
For Phase II SSA data set, grid corner locations are (UTM zone 13)Corner Northing (UTM) Easting (UTM) ------------------------------------------------------ NW 6000000 488000 NE 6000000 528000 SW 5964000 488000 SE 5964000 528000
For Phase III regional data set, grid corner locations are:Corner Latitude (degrees) Longitude (degrees) ----------------------------------------------------------- NW 57°N 107°W NE 57°N 96°W SW 52°N 107°W SE 52°N 96°W7.1.2 Spatial Coverage Map
A map of the geographic locations of the surface station sites, together with boundaries of the BOREAS region, study areas, original modeling region, and the Saskatchewan and Grass-Burntwood watershed basins (used for routing model validation) can be found in the GIF file 'locate.gif' (see below). Boundaries of GOES and Rain Radar coverage maps are not included.
7.1.3 Spatial Resolution
The resolution is 2 x 2 km for Phase II study area data sets, and 10' horizontal (longitude) by 5' vertical (latitude) for Phase III regional data set.7.1.4 Projection
Projection is UTM for the Phase II study area data sets, and Geographic (latitude-longitude) for the Phase III regional data set.7.1.5 Grid Description
The NSA grid is 17 columns (longitude) by 16 rows (latitude). The SSA grid is 20 columns (longitude) by 18 rows (latitude). The regional grid is 66 columns (longitude) by 60 rows (latitude). The images are all binary with each pixel being stored as a four-byte binary float.
7.2 Temporal Characteristics
7.2.1 Temporal Coverage
Data gridded were from January 1, 1994 through December 31, 1996.7.2.2 Temporal Coverage Map
Not applicable.7.2.3 Temporal Resolution
Data were gridded at an hourly interval. Temporal units are in GMT.
7.3 Data Characteristics
7.3.1 Parameter/Variable7.4 Sample Data RecordVariable Image prefix --------------------------- ------------ Air pressure Pres Air temperature Ta Dew point temperature Td Wind speed U Wind direction Ud Precipitation Prec Incoming SW radiation Rsi Incoming LW radiation Lwi7.3.2 Variable Description/Definition
See section 7.3.1. Times are in GMT using backward time tag convention (i.e., time tag n indicates data record applies to hourly period n to n+1).
7.3.3 Unit of Measurement
Variable Measurement Units ------------------------- ----------------- Air temperature C Dew point temperature C Wind direction Degrees Wind speed m/s Air pressure kPa Incoming SW radiation Rsi Incoming LW radiation Lwi Precipitation mm/h7.3.4 Data Source
For data sources we refer to documentation files of individual input data sets.
7.3.5 Data Range
Variable Minimum Maximum Missing value Value value indicator -------- --------- ---------- ------------- Ta -46.013359 37.548920 -9999 Td -53.659573 47.275021 -9999 Ud 0.000008 360.000000 -9999 U 0.000019 42.264545 -9999 Pres 86.865944 101.601524 -9999 Rsi -4.899975 1042.467407 -9999 Lwi 55.841991 447.747894 -9999 Prec 0.000000 176.934235 -9999
8.1 Data Granularity
Data exist for every hour when available.
The hour files have been organized into daily folders/directories. Each
filename has the following structure:
yy-mm-dd_hh_sss_V2.bin
where yy is the two-digit year, mm is the 2-digit month, dd is the 2-digit
day, hh is the hour of day (in GMT), sss is the site (nsa or ssa), and
V2 is the variable (such as "pres", with a 2 or 3 following it for Phase
2 or Phase 3 data).
Each of the eight variables has the
same directory structure. Each variable has three yearly subdirectories
(94, 95, and 96). Each yearly subdirectory contains 12 monthly Zip archive
files. Each of the Zip archive files contains daily subdirectories, which
each contain the 24 hourly data files.
For example, Northern Study Area Pressure
on 1 November 1995 at 14:00 UTC would be found in the following Zip file:
gridded_mesonet_p2/nsa/pres2_95_nsa/95-11-00_nsa_pres2.zip
Once decompressed, this Zip file would yield a directory for November 1995, and the specific file would be:
95-11-00_nsa_pres2/95-11-01_nsa_pres2/95-11-01_14_nsa_pres2.bin
8.2 Data Format(s)
The data are stored as 4-byte binary
float images, one image per hour per variable (the data may need to be byte
swapped to display properly). The regional grid is 66
columns by 60 rows. The NSA grid is 17 columns by 16 rows and the SSA grid
is 20 columns by 18 rows.
For this archive, the image files have
been compressed with the MS Windows-standard Zip compression scheme. These
files were compressed using Aladdin's DropZip on a Macintosh. DropZip uses
the Lempel-Ziv algorithm (Welch, 1994), also used in Zip and PKZIP programs.
The compressed files may be uncompressed using PKZIP (with the -expand
option) on MS Windows and UNIX, or with StuffIt Expander on the Mac OS.
You can get newer versions from the PKZIP Web site at http://www.pkware.com/download-software/
[Internet Link].
9.1.1 Derivation Techniques and Algorithms
Not applicable.
9.2 Data Processing Sequence
9.2.1 Processing Steps
First the station data were converted to a common format, temporal resolution, and into common units. Using this derived data set the interpolation was done.9.2.2 Processing Changes
Not applicable.
9.3 Calculations
9.3.1 Special Corrections/Adjustments
All station observed values that were outside reasonable limits were found to correspond to be measurement errors. For all variables these values are:Variable Minimum Maximum Allowed Allowed -------- ------- ------- U 0 120 Ud 0 360 Ta -60 60 Td -60 60 Rsi -5 1200 Lwi 50 600 Pres 85 110 Prec 0 200Wind directions were afterward corrected in range 0-360 degrees.9.3.2 Calculated Variables
Air temperature, dew point temperature, wind speed, wind direction, air pressure, incoming long wave radiation, incoming short wave radiation and precipitation.
9.4 Graphs and Plots
Not applicable.
10.2 Data Quality Assessment
10.2.1 Data Validation by SourceReturn to top of document.
For this purpose we refer to the documentation files of the individual data sources. See section 3.0.10.2.2 Confidence Level/Accuracy Judgment
The level of accuracy of the interpolated data is essentially the same as the accuracy of the station data in the southern part of the region, in the north additional error can be expected due to the scarcity of surface stations.10.2.3 Measurement Error for Parameters
For this purpose we refer to the documentation files of the individual data sources.10.2.4 Additional Quality Assessments
Phase II & III gridded data sets were checked as follows, with few inconsistencies found using these procedures:10.2.5 Data Verification by Data Center
- Extracted time series for various grids were compared with original station data for that grid -- this was done for each of BOREAS flux towers, for 2 AES stations, for 2 SRC/AMS stations, and for 2 Forestry Canada stations.
- Regional averages were calculated & checked for inconsistencies.
- Regional average monthly diurnal cycles of each individual variable were compared to ECMWF Numerical Weather Prediction (NWP) data.
Random files were checked for format and size consistency.
11.2 Known Problems with the Data
See section 10.1.
11.3 Usage Guidance
Care has been taken in constructing
the best data set possible. The data is not "error-free". The user should
thus make sure that the data set is appropriate for his or her modeling
purposes.
11.4 Other Relevant Information
None.
14.2 Software Access
Zip is available from many Web sites
across the Internet. You can get newer versions from the PKZIP Web site
at http://www.pkware.com/download-software/
[Internet Link]. Versions of the decompression software for MS Windows,
Mac OS, and several varieties of UNIX systems are included in this archive.
ORNL DAAC User Services
Oak Ridge National Laboratory
(865) 241-3952
ornldaac@ornl.gov
ornl@eos.nasa.gov
15.2 Procedures for Obtaining Data
BOREAS data may be obtained through
the ORNL DAAC World Wide Web site at http://www.daac.ornl.gov/
[Internet Link] or users may place requests for data by telephone
or by electronic mail.
15.3 Output Products and Availability
Requested data can be provided electronically
on the ORNL DAAC's anonymous FTP site or on various media including, CD-ROMs,
8-mm tapes, or diskettes.
16.2 Film Products
None.
16.3 Other Products
The BOREAS hydromet model intercomparison
forcing data are all obtainable through CD-ROM. Contact Eric Smith in order
to obtain this CD-ROM.
17.2 Journal Articles and Study Reports
The data set processing, intercomparison
with ECMWF data, and preliminary model results using the data set are described
in:
Pauwels, V.R.N., Examination of the Sources of Uncertainty in Land-Atmosphere Model Results for Boreal Ecosystems, Ph.D. thesis, Department of Civil Engineering and Operations Research, Princeton University, 1999.
Pauwels, V.R.N., J. Gu, B. Nijssen, A.K. Betts, K.R. Snelgrove, E.A. Whidden, N. Kouwen, D.P. Lettenmaier, E.A. Smith, E.D. Soulis, and E.F. Wood, A multiscale surface meteorological data set for BOREAS, in preparation.
Sellers, P., F. Hall. 1994. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1994-3.0, NASA BOREAS Report (EXPLAN 94).
Sellers, P., F. Hall. 1996. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1996-2.0, NASA BOREAS Report (EXPLAN 96).
Sellers, P., F. Hall, K.F. Huemmrich. 1996. Boreal Ecosystem-Atmosphere Study: 1994 Operations. NASA BOREAS Report (OPS DOC 94).
Sellers, P., F. Hall, K.F. Huemmrich. 1997. Boreal Ecosystem-Atmosphere Study: 1996 Operations. NASA BOREAS Report (OPS DOC 96).
Sellers, P., F. Hall, H. Margolis, B. Kelly, D. Baldocchi, G. den Hartog, J. Cihlar, M.G. Ryan, B. Goodison, P. Crill, K.J. Ranson, D. Lettenmaier, and D.E. Wickland. 1995. The boreal ecosystem-atmosphere study (BOREAS): an overview and early results from the 1994 field year. Bulletin of the American Meteorological Society. 76(9):1549-1577.
Sellers, P.J., F.G. Hall, R.D. Kelly, A. Black, D. Baldocchi, J. Berry,
M. Ryan, K.J. Ranson, P.M. Crill, D.P. Lettenmaier, H. Margolis, J. Cihlar,
J. Newcomer, D. Fitzjarrald, P.G. Jarvis, S.T. Gower, D. Halliwell, D.
Williams, B. Goodison, D.E. Wickland, and F.E. Guertin. 1997. BOREAS in
1997: Experiment Overview, Scientific Results and Future Directions. Journal
of Geophysical Research 102(D24): 28,731-28,770.
17.3 Archive/DBMS Usage Documentation
None.
AES - Atmospheric Environment Service of Canada ASCII - American Standard Code for Information Interchange BOREAS - BOReal Ecosystem-Atmosphere Study BORIS - BOREAS Information System DAAC - Distributed Active Archive Center ECMWF - European Center for Medium-Range Weather Forcasting EOS - Earth Observing System EOSDIS - EOS Data and Information System GMT - Greenwich Mean Time GSFC - Goddard Space Flight Center HYD - Hydrology IFC - Intensive Field Campaign NASA - National Aeronautics and Space Administration NSA - Northern Study Area NWP - Numerical Weather Prediction ORNL - Oak Ridge National Laboratory PANP - Prince Albert National Park SSA - Southern Study Area URL - Uniform Resource Locator (a World Wide Web address)Return to top of document.
Wood, E., and V. Pauwels. 2001. BOREAS Follow-On HMet-02 Area and Regional Hourly Gridded Met[eorological] Data, 1994-1996. Available on-line [http://www.daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A.
Keywords:
ECMWF
Surface Pressure
Surface Temperature
Surface Flux
Precipitation
Albedo
Wind direction
Wind speed
Radiation
GOES Images