Pre-LBA Anglo-Brazilian Amazonian Climate Observation Study (ABRACOS) Data

The data set presents the principal data from the Anglo-BRazilian Amazonian Climate Observation Study (ABRACOS) (Gash et al, 1996) and provides quality controlled information from five of the study topics considered by the project in five zipped files containing ASCII text data. The five study topics include Micrometeorology, Climate, Carbon Dioxide and Water Vapor, Plant Physiology, and Soil Moisture. The objectives of the ABRACOS were to monitor Amazonian climate and improve the understanding of the consequences of deforestation and to provide data for the calibration and validation of GCMs and GCM sub-models of Amazonian forest and post-deforestation pasture (Shuttleworth et al, 1991). Three areas were instrumented, each with different soils, dry season intensities and deforestation densities (Gash et al, 1996). In each area, an automatic weather station and soil moisture measurement equipment were installed: in a primary forest site and in nearby cattle pasture, for monitoring climate and soil status throughout the year. Additional intensive periods of study (or Missions), of varying duration, were operated at these sites: for calibration purposes, to understand the physical processes relevant to each site, and for detailed comparisons between sites. These data were collected under the ABRACOS project and made available by the UK Institute of Hydrology and the Instituto Nacional de Pesquisas Espaciais (Brazil). ABRACOS is a collaboration between the Agencia Brasileira de Cooperacao and the UK Overseas Development Administration. The processed, quality controlled and integrated data in the documented Pre-LBA data sets were originally published as a set of three CD_ROMs (Marengo and Victoria, 1998) but are now archived individually.

Pre-LBA Data Set Collection Initiative

The Pre-LBA data set collection was dedicated to providing information to the LBA research community about existing data that have been collected in Amazonia during the 20 years prior to 1998. The main goal of this activity was to compile and document existing data sets in a consistent manner and make them available prior to the beginning of the LBA experiment. 

The data sets compiled included satellite imagery, micrometeorological observations, near surface and upper-air atmospheric conditions, surface biophysical and hydrological measurements obtained from the 1970s to the 1990s in a number of field experiments. Data were collected for several intensive field capaigns, during the rainy and dry seasons, and other periods that vary from short intensive field campaigns to several years worth of observations, measured sometimes with a time resolution of 5 minutes and 1 hour.

There are five folders containing a combined 146 files in text (.txt) format.

Citation:

The original CD-ROM citation is as follows:

Marengo, J.A., and R.L. Victoria. 1998. Pre-LBA Data Sets Initiative, 3 vols. [Pre-Large-Scale Biosphere-Atmosphere Experiment in Amazonia Data Sets Initiative, 3 vols.]. CD-ROM. Centro de Previsao de Tempo e Estudios Climaticos, Instituto Nacional de Pesquisas Espaciais (CPTEC/INPE) [Center for Weather Forecasting and Climate Study, National Institute for Space Research], Sao Paulo, Brazil.

The data set presents the principal data from the Anglo-BRazilian Amazonian Climate Observation Study (ABRACOS) (Gash et al, 1996) and provides quality controlled information from five of the study topics considered by the project in five zipped files containing ASCII text data. The five study topics include Micrometeorology, Climate, Carbon Dioxide and Water Vapor, Plant Physiology, and Soil Moisture. The objectives of the ABRACOS were to monitor Amazonian climate and improve the understanding of the consequences of deforestation and to provide data for the calibration and validation of GCMs and GCM sub-models of Amazonian forest and post-deforestation pasture (Shuttleworth et al, 1991).

Three areas were instrumented, each with different soils, dry season intensities and deforestation densities (Gash et al, 1996). In each area, an automatic weather station and soil moisture measurement equipment were installed: in a primary forest site and in a nearby cattle pasture, for monitoring climate and soil status throughout the year. Additional intensive periods of study (or Missions), of varying duration, were operated at these sites: for calibration purposes, to understand the physical processes relevant to each site, and for detailed comparisons between sites. These data were collected under the ABRACOS project and made available by the UK Institute of Hydrology and the Instituto Nacional de Pesquisas Espaciais (Brazil). ABRACOS is a collaboration between the Agencia Brasileira de Cooperacao and the UK Overseas Development Administration. The processed, quality controlled and integrated data in the documented Pre-LBA data sets were originally published as a set of three CD_ROMs (Marengo and Victoria, 1998) but are now archived individually.

Pre-LBA Data Set Collection Initiative

The Pre-LBA data set collection was dedicated to providing information to the LBA research community about existing data that have been collected in Amazonia during the 20 years prior to 1998. The main goal of this activity was to compile and document existing data sets in a consistent manner and make them available prior to the beginning of the LBA experiment. 

The data sets compiled included satellite imagery, micrometeorological observations, near surface and upper-air atmospheric conditions, surface biophysical and hydrological measurements obtained from the 1970s to the 1990s in a number of field experiments. Data were collected for several intensive field capaigns, during the rainy and dry seasons, and other periods that vary from short intensive field campaigns to several years worth of observations, measured sometimes with a time resolution of 5 minutes and 1 hour.

Citation:

The original CD-ROM citation is as follows:

Marengo, J.A., and R.L. Victoria. 1998. Pre-LBA Data Sets Initiative, 3 vols. [Pre-Large-Scale Biosphere-Atmosphere Experiment in Amazonia Data Sets Initiative, 3 vols.]. CD-ROM. Centro de Previsao de Tempo e Estudios Climaticos, Instituto Nacional de Pesquisas Espaciais (CPTEC/INPE) [Center for Weather Forecasting and Climate Study, National Institute for Space Research], Sao Paulo, Brazil.

Project: Large Scale Biosphere-Atmosphere Experiment (LBA-ECO)

The Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) is an intensive scientific investigation of the tropical rainforest of Brazil and portions of adjacent countries. Like FIFE and BOREAS, this project uses intensive remote-sensing techniques and ground-based experiments to investigate the atmosphere-biosphere-hydrosphere dynamics of this large tropical region. The LBA Project encompasses several scientific disciplines, or components. The LBA-ECO component focuses on the question: "How do tropical forest conversion, regrowth, and selective logging influence carbon storage, nutrient dynamics, trace gas fluxes, and the prospect for sustainable land use in Amazonia?"

Related Publications:

Gash, J.H.C., Nobre, C.A., Roberts, J.M. and Victoria, R.L. (Eds), 1996. Amazonian Deforestation and Climate. J. Wiley & Sons, Chichester.

Shuttleworth, W.J., Gash, J.H.C., Roberts, J.M., Nobre, C.A., Molion, L.C.B. and Ribeiro, N.M.G., 1991. Post-deforestation Amazonian climate: Anglo-Brazilian research to improve prediction. J. Hydrol. 129: 71-86. https://doi.org/10.1016/0022-1694(91)90045-J

Acknowledgments:

These data were originally collected under the ABRACOS project and made available by the UK Institute of Hydrology and the Instituto Nacional de Pesquisas Espaciais (Brazil). ABRACOS is a collaboration between the Agencia Brasileira de Cooperacao and the UK Overseas Development Administration. 

Spatial Coverage: Data taken from five observation sites in Rondonia, Brazil and in Para, Brazil.

Spatial Resolution: Point Resolution

Temporal Coverage: 1991/01/01 to 1996/12/31

Temporal Resolution: 30 min

Study Area:

Southernmost_Latitude	Northernmost_Latitude	Westernmost_Latitude	Easternmost_Latitude
-18	5	-75	-46

Data File Information:

This data set gives quality controlled information from five of the study topics considered by the project: Micrometeorology, Climate, Carbon Dioxide and Water Vapor, Plant Physiology, and Soil Moisture. 

There are five folders containing a combined 146 files in text (.txt) format.

Micrometeorology and Evaporation Data from Five Observation Sites

NS Fazenda Nossa Senhora, nearJi-Parana, Rondonia 
BS Fazenda Boa Sorte, Near Maraba, Para 
RJ Reserva Jaru, near Ji-Parana, Rondonia 
RV Reserva Vale, near Maraba, Para

(Summary was adapted from the ABRACOS Home Page: http://www.cptec.inpe.br/abracos/micromet.html)

Detailed descriptions of the ABRACOS weather stations and micrometeorology data are available from companion file, micromet.pdf (http://daac.ornl.gov/daacdata/lba/physical_climate/ABRACOS/comp/minromet.pdf)

Data files have been compiled and compressed in a single file, MICROMET_EVAP.zip.

HEADER FOR MICROMETEOROLOGY DATA FILES

Data File Column	Parameter Description
Column 1	Julian day number
Column 2	Hour (local)
Column 3	Total incoming short-wave (W/m^2)
Column 4	Reflected short-wave (W/m^2)
Column 5	Net radiation (W/m^2)
Column 6	Soil heat flux (W/m^2)
Column 7	Air temperature (°C)
Column 8	Specific humidity (g/kg)
Column 9	Wind speed (m/s)
Column 10	Wind direction (degrees arc, clockwise from North)
Column 11	Friction velocity (m/s)
Column 12	Stability parameter, z/L, where L is Monin-Obukhov length
Column 13	Integrated stability correction parameter for sensible heat flux
Column 14	Integrated stability correction parameter for momentum flux
Column 15	Aerodynamic conductance for heat fluxes (mm/s)
Column 16	Bulk surface conductance for heat fluxes (mm/s)
Column 17	Latent Heat Flux (W/m^2)
Column 18	Sensible Heat Flux (W/m^2)
Column 19	EITHER Pasture: soil moisture in the root zone (m3/m^3)
Column 20	OR Forest: change in biomass heat storage (W/m^2)
Column 21	Rainfall (mm)
Column 22	Soil temperature at 10cm (some pasture sites only) (°C)
Column 23	Soil temperature at 20cm (some pasture sites only) (°C)
Column 24	Soil temperature at 40cm (some pasture sites only) (°C)

Climate Data from Seven Observation Sites

AB-C[sitecode].[year][A or B]

A and B correspond the first and second half of the year.

Site Codes: 
FD Fazenda Dimona Manaus 
NS Fazenda Nossa Senhora Aparecida Ji-Parana 
BS Fazenda Boa Sorte Maraba 
RD Reserva Ducke Manaus 
RJ Reserva Jaru Ji-Parana 
RV Reserva Vale do Rio Doce Maraba 
MS Urban climate Manaus 

(Summary was adapted from the ABRACOS Home Page: http://www.cptec.inpe.br/abracos/climate.html)

Detailed descriptions of the ABRACOS weather stations and data are available from the companion file, climate.pdf.  (http://daac.ornl.gov/daacdata/lba/physical_climate/ABRACOS/comp/climate.pdf)

Data files have been compiled and compressed in a single file, CLIMATE.zip.

HEADER FOR CLIMATE DATA FILES

Data File Column	Parameter Description
Column 1	Site code
Column 2	Year
Column 3	Day Number
Column 4	Time GMT
Column 5	Incoming solar radiation (direct + diffuse)(W/m^2)
Column 6	Reflected solar radiation (W/m^2)
Column 7	Net all-wave radiation (W/m^2)
Column 8	Wet bulb temperature (°C)
Column 9	Air temperature (°C)
Column 10	Wind speed (m/s)
Column 11	Wind direction (Degrees from the North)
Column 12	Soil heat flux (W/m^2)
Column 13	Rainfall (mm)

(http://yabae.cptec.inpe.br/abracos/carb_flux.html)Forest Carbon Dioxide and Water Vapor Flux Data

(http://daac.ornl.gov/daacdata/lba/physical_climate/ABRACOS/comp/carb_flux.pdf)

HEADER FOR CARBON DATA FILES

Data File Column	Parameter Description
Column 1	Year
Column 2	Day number
Column 3	Local time (hours)
Column 4	Local time (minutes)
Column 5	N.B. Local Time = GMT-4 hours. The time stated is the time at the END of each half-hour period
Column 6	Sensible heat flux (W/m2)
Column 7	Evaporation (mmol/m2/s)
Column 8	N.B. These H and E fluxes have been compared with those of the coincident micrometeorology system (Wright et al 1996) and used in deriving the agreed fluxes which are contained in FORSTM3_DAT and FORSTM45_DAT(FORST_EXE).
Column 9	Therefore, the fluxes given here should only be considered as raw output from this system, and only the FORST’ files should be used as the best estimate of latent and sensible heat flux from this site.
Column 10	CO2 turbulent flux (mmol/m2/s)
Column 11	Friction velocity (m/s)
Column 12	Standard deviation of u-component of wind velocity
Column 13	Standard deviation of v-component of wind velocity
Column 14	Standard deviation of w-component of wind velocity
Column 15	Mean value of u (m/s) u positive is wind GOING IN the direction 224 degrees
Column 16	Mean value of v (m/s) v positive is wind GOING IN the direction 314 degrees
Column 17	Mean value of w (m/s) w positive is wind GOING UPWARDS
Column 18	Mean virtual temperature from sonic anemometer (K)
Column 19	Mean CO2 concentration (parts per million)
Column 20	Mean H2O concentration (parts per thousand)
Column 21	Mean tube lag on CO2 measurements (in units of 1/20.8 secs)
Column 22	Mean tube lag on H2O measurements (in units of 1/20.8 secs)
Column 23	The following 4 columns appear in AB-ROND93_DAT only. Mean within-canopy CO2 concentration
Column 24	Mean within-canopy CO2 storage flux (positive = flux OUT of canopy)
Column 25	Mean above-canopy wind speed
Column 26	Mean Monin-Obukhov length, L

 

Plant Physiology Data

Self-explanatory tabulation of pasture physical properties including height, leaf, and stem area index, leaf stem and dead material dry biomass.

These files contain leaf physiology data from the Ji-Parana and Manaus pasture (NS and FD) and Ji Parana forest (RJ).

PHOTOSYNTHETICALLY ACTIVE RADIATION (PAR) - 20 RD or 17 RJ 6-character columns in which ten minute PAR is given as an integer in micro-mols m-2 s-1.

TEMPERATURE, HUMIDITY AND WIND SPEED (TDU) - Temperature and humidity deficit measured using aspirated psychrometers (IH, Wallingford UK) and wind speed using type A100 anemometers (Vector instruments, Rhyl, UK).

http://www.cptec.inpe.br/abracos/physio.html)

Additional information about the ABRACOS plant physiology datasets including dataset format is available from the companion file, physio.pdf.  (http://daac.ornl.gov/daacdata/lba/physical_climate/ABRACOS/comp/physio.pdf)

Data files have been compiled and compressed in a single file, PHYSIOLOGY.zip.

HEADER FOR PHYSIOLOGY DATA FILES

Data File Column	Parameter Description
Column 1	Vegetation type
Column 2	Additional information relating to the sampled leaves, including ‘SUN', 'SHADE', 'OLD' (leaves), 'NEW' (leaves). '#' indicates no information.
Column 3	For Pasture Number of plots sampled for Forest Number of leaves sampled.
Column 4	Decimal local time (hours)
Column 5	Height from the ground (m)
Column 6	Photosynthetically active radiation (PAR) in micro-mols m-2 s-1
Column 7	Air temperature near the leaf (Ta) in °C
Column 8	Leaf temperature (Tl) in °C
Column 9	Stomatal conductance (gs) in millimols m-2 s-2
Column 10	Net photosynthesis (pn) in micromoles m-2 s-1
Column 11	Concentration of intercellular carbon dioxide (CO2) in micromoles m-2 s-1
Column 12	Leaf evaporation
Column 13 – 19	Standard deviations of the mean values appearing in columns 6-12
Column 20	Decimal local time (hours) for the leaf water potential measurement that was closest in time to the current data line
Column 21	Leaf water potential in MPa
Column 22	Standard deviation of leaf water potential

 

 

Soil Moisture Data

These data sets consist of soil moisture readings measured at six sites in Brazil. Readings were taken close to each automatic weather station (AWS) except at Manaus Forest where data was recorded in primary forest close to the pasture site.

(Summary was adapted from the ABRACOS Home Page: http://www.cptec.inpe.br/abracos/soil.html)

Additional information about the ABRACOS soil moisture data is available in the companion file, soil.pdf.  (http://daac.ornl.gov/daacdata/lba/physical_climate/ABRACOS/comp/soil.pdf)

Data files have been compiled and compressed in a single file, SOIL_PHYSICS.zip.

---

Data file format information from the companion file, soil.pdf.

• The first three columns of each file give the year, day number, and time (decimal hour) of measurement
• Thereafter, the remaining columns contain the mean soil moisture, at various depths, in units of moisture volume fraction (m3/m3). The means are calculated as the linear average of all access tubes at each site, with the exception of Reserva Jaru (see notes). 

The objectives of the ABRACOS were to monitor Amazonian climate and improve the understanding of the consequences of deforestation and to provide data for the calibration and validation of GCMs and GCM sub-models of Amazonian forest and post-deforestation pasture (Shuttleworth et al, 1991).

No particular methods are disclosed on the quality assessment of the data within this dataset.

Site Descriptions:
   a. Reserva Ducke, Manaus
Reserva Ducke (2 57'S, 59 57'W) is an area of protected primary forest, 25 km north-east of Manaus at 80 m above mean sea level. The experimental site was also the site of the Amazon Regional Micrometeorological Experiment in the early 1980s (see Shuttleworth et al. (1991) for a summary), but was re-established for ABRACOS in late 1990. The mean forest canopy is 35 m high, but some trees reach up to 40 m. The forest in Reserva Ducke, in common with the other two forest sites studied, is made up of a large variety of tree species. The tallest species in the area around the tower are Piptadenia suaveolens Miq., Licania micrantha Miq., Bocoa viridiflora (Ducke) Cowan, Naucleopsis glabra Spruce ex Baill and Enterolobium schomburgkii Benth. The site is surrounded by undisturbed forest for at least 5 km. An extensive description of the site is given by Shuttleworth et al. (1984) and Roberts et al. (1990). The automatic weather station is mounted at the top of a 45 m aluminum tower.

   b. Fazenda Dimona, Manaus
      Pasture
Fazenda Dimona (2 19'S, 60 19'W) is a cattle ranch located about 100 km north of Manaus. The ranch is a 10 km square clearing at an altitude of 120 m above mean sea level. It was created in about 1975 by felling and burning an area of primary forest. The ground was planted with pasture grass (Brachiaria decumbens and Brachiaria humidicola) but 11% of the surface area is bare soil and many felled tree trunks still remain, covering 5% of the ground area (Wright et al. 1992). The pasture has been regularly burnt to destroy the vigorous regrowth of bushes. Since late 1992, however, this practice has ceased and the pasture is becoming rapidly overgrown. Instrumentation was installed at the site in September 1990. The automatic weather station is mounted at the surface. Descriptions of the site are given by McWilliam et al. (1993) and Wright et al. (1992) together with the results of biomass and micrometeorological measurements respectively.

    Forest
Soil moisture access tubes were installed in primary forest close (900m) to the Pasture of Fazenda Dimona and the above site location details apply. See Hodnett et al. 1995.

   c. Reserva Vale do Rio Doce, Maraba
This forest site (5 45'S, 49 10'W) was established in July 1991 in the forest reserve of the Companhia Vale do Rio Doce at 150 m above sea level 50 km to the south of Maraba. The forest reserve is 17,000 hectares in area and is to a large degree uncut, but is almost completely surrounded by cleared areas. The automatic weather station is mounted on top of a 52 m tower positioned to the east of a mature Brazil nut tree (Bertholletia excelsa HBK) with a height of 49 m, but the continuous forest canopy, consisting mainly of Inga alba (SW) Willd, Pourouma guianensis Aubl., Guarea guidonia (L.) Sleumer and Sagotia brachysepaia (Muell Arg.) R.Secco in the area surrounding the tower, is much lower, around 20 to 25 m. The abundance of the large Brazil nut trees is a characteristic feature of the forests in the Maraba region and means that the structure of the canopy in this area differs considerably from that of the Reserva Ducke or Reserva Jaru sites. See Roberts et al (1996), Sa et al (1996) and Solamao (1991).

   d. Fazenda Boa Sorte, Maraba
Fazenda Boa Sorte (5 10'S, 48 45'W) is a cattle ranch 50 km to the north-east of Maraba at 170 m above mean sea level and was deforested sometime before 1975. The site was established in July 1991 and is a large area of pasture covered predominantly with tropical grass (Panicum maximum Jacq.) and small patches of bare soil: a red-yellow sandy loam Latosol (Oxisol). The ranchland has numerous Babau palms which, because of their resistance to fire, commonly remain after forest clearance, and as such is typical of clearings in the Maraba region. See Roberts et al (1996), Sa et al (1996). The site differs from Fazenda Dimona in that the dead tree trunks and stumps were removed in the initial clearance. The automatic weather station is mounted at the top of a 6 m aluminum tower.

   e. Reserva Jaru, Ji-Parana
Reserva Jaru (10 05'S, 61 55'W) is a forest reserve owned by the Brazilian Environmental Protection Agency (IBAMA) and is located about 80 km north of Ji-Parana at 120 m above sea level. The 52 m forest tower was installed and instrumented in October 1991. The mean height of the forest canopy is 33 m. The tallest tree species in the area immediately surrounding the tower are Cedrella odorata, Inga sp., Dioclea cf bicolor Bth., Strychnos amazonicus Krukoff, Protium polybotrium and Leonia glycicarpa Ruiz, see McWilliam et al. (1996) and Roberts et al. (1996). The automatic weather station was mounted at the top of the tower.

   f. Fazenda Nossa Senhora da Aparecida, Ji-Parana
This site (10 45'S, 62 22'W) was established in October 1991 on a cattle ranch 220 m above sea level about 50 km east-north-east of Ji-Parana. The site was deforested in about 1977 and is in the center of an area of about 50 km in radius which has been largely cleared. The grass (Brachiaria brizantha) is clumpy and the original planting rows can still be clearly seen from above, see McWilliam et al. (1996) and Roberts et al. (1996). The area of bare soil was surveyed in April 1993 and found to form 12% of the surface area. The ranchland is similar in appearance to Fazenda Boa Sorte with several palms and, in contrast to Fazenda Dimona, with very few dead tree trunks. The pasture had been burnt in the month prior to equipment installation, but it was not burnt again during ABRACOS. The automatic weather station is mounted in a similar way to that at Fazenda Boa Sorte.

   g. Manaus City
This urban weather station site was established in October 1990 close to the Intituto Nacional de Pesquisas da Amazonia (INPA) in Manaus (60 10'W, 3 6'S) to assess the effect of urbanization on climate in Amazonia. The site is representative of the urban area of Manaus, but not in the center of that area, see Maitelli and Wright (1996). The weather station was installed over an area of grass and so care should be taken with interpretation of data such as net radiation and reflected solar radiation. These parameters should not be assumed to be representative of the urban landscape as a whole. The weather station is mounted at the surface similar to the Fazenda Dimona weather station. For reasons of security and to avoid damage by livestock, the instruments at all the ranchland sites are located within wire fenced enclosures of about 10 m by 10 m. However, to ensure that the measurements are as representative as possible of the grazed areas, the grass within these enclosures is regularly monitored and cut when necessary to keep it of similar length to that outside the enclosures.
 

Micrometeorology:
Hourly estimates of evaporation, heat flux and conductances supported by climate data and calibrated estimates of the hourly momentum flux and atmospheric stability. The data were recorded during the intensive study periods at 5 of the 6 ABRACOS sites and range in duration from 3 weeks to 3 months.

Instruments used include solarimeters, REBS net all-wave radiometer, a platinum resistance thermometer, a platinum resistance wet-bulb thermometer, and a manual rain gauge.
   

Climate:
The data were recorded as hourly averages, or in the case of rainfall an hourly total, by a Campbell Scientific CR10 logger.

   Solar Radiation
Kipp and Zonen (Delft, The Netherlands) CM-5 solarimeter recorded radiation of wavelengths 0.3 to 3 micrometers. A similar sensor but inverted was used to measure the reflected solar radiation. The error in these measurements is estimated to be about plus or minus 1%.

   Net Radiation
Net all-wave radiation measured by a single dome Q*6 radiometer (Radiation Energy Balance Systems, Seattle, USA). A comparison was carried out between these instruments and the agreement between was found to be better than their probable calibration errors of about plus or minus 3%.

   Wet bulb temperature and air temperature
The wet bulb and air temperatures were measured using aspirated platinum resistance thermometers housed in an Institute of Hydrology design psychrometer screen. The thermometers were calibrated against a standard and are accurate to plus or minus 0.1 degrees C.

   Wind speed and direction
Wind speed was measured by an DWR-201 anemometer and wind direction by a DWD-103 wind vane both manufactured by Didcot Instruments Ltd, Abingdon, UK. The anemometer has metal cups of robust design and a starting speed of 0.3 to 0.4 meters per second and a stalling speed of 0.2 meters per second.

   Soil heat flux
The soil heat flux was measured with two model 610 soil heat flux plates (Thornthwaite, Elmer, New Jersey, USA), which were installed at a depth of 5 mm. The value recorded in the dataset is an average of the values from the two instruments.

   Rainfall
Rainfall was measured using a 0.2 mm resolution tipping bucket rain gauge (Didcot Instrument Company, Abingdon UK). The instrument stood on a concrete slab at the surface. For the sites at which the weather station was mounted on a tower, the raingauge was connected by a tube to a funnel mounted at the same height as the weather station.
 

Carbon Dioxide and Water Vapor:
The files AB-FXC92.DAT and AB-FXC93.DAT contain the 30-minute average carbon dioxide and water vapor flux data measured over the tropical forest at Reserva Jaru, Ji-Parana, using an eddy covariance system developed by the Institute of Ecology and Resource Management, Edinburgh University, UK. The files also contain the mean wind component and turbulence data derived by this system.

The eddy covariance system consisted of a fast-response closed-path infra-red gas analyzer to measure carbon dioxide and water vapor (Li 6262, Li-Cor, Lincoln, Nebraska); a 3- dimensional sonic anemometer to measure the vertical component of wind (Solent A1002R, Gill Instruments, Lymington, UK); a pumping unit to draw air through 5m of 5.5 mm diameter tubing (Dekabon 1300, Deane & Co., Glasgow, UK); and a 386 laptop' computer with software EDDYSOL' to enable the flux calculations to be made as half-hour averages in real time (Moncrieff et al. 1996, Grace et al. 1995).

 

Plant Physiology:  
Grass was sampled for analysis using a 0.5m x 0.5m quadrat which was randomly placed within the area monitored for water vapour flux data. All vegetative material within the quadrat was removed and analyzed for leaf area and dry biomass within one or two days of removal. Data were recorded at Fazenda Dimona during the first two missions (M1 and M2) where the grass species were Brachiaria decumbens and B. Humidicola (McWilliam et al 1993). All other data is from Fazenda Nossa Senhora (M3, M4 and M5) where the grass species was Brachiaria Brizantha.

N.B. The M4 leaf and stem area indices were estimated using calculations of specific leaf area obtained from the M3 data. Temperature and humidity deficit were measures using aspirated psychrometers (IH, Wallingford UK) and wind speed using type A100 anemometers (Vector instruments, Rhyl, UK). The data files contain ten-minute averages in free format with 7-character columns.

Soil Moisture:
Soil moisture was measured close to the automatic weather station (AWS) using a neutron probe soil moisture meter. The only exception to this was the 'Manaus forest' data which was recorded in the primary forest close to the pasture site (FD) rather than at the Manaus forest AWS site (RD), see Hodnett et al. (1995). For this reason, an extra code is introduced, FDF, for 'Forest at Fazenda Dimona'. Further details of all sites are given in AB-AWS.TXT. The soil moisture at each access tube was read approximately every 7 days and with increased frequency during the intensive data missions (see AB-MMET.TXT).

 

This information was taken from the companion files. More information concerning the methods, materials, and data acquisition can be found in the referenced materials and the companion files of this dataset.

Gash, J.H.C., Nobre, C.A., Roberts, J.M. and Victoria, R.L. (Eds), 1996. Amazonian Deforestation and Climate. J. Wiley & Sons, Chichester.

Shuttleworth, W.J., Gash, J.H.C., Roberts, J.M., Nobre, C.A., Molion ,L.C.B. and Ribeiro, N.M.G., 1991. Post-deforestation Amazonian climate: Anglo-Brazilian research to improve prediction. J. Hydrol. 129: 71-86.

 

Micrometeorology and Evaporation from Five Observation Sites

Arya, S.P., 1988. Introduction to micrometeorology. Academic Press (London). pp307.

Brutsaert, W. 1984. Evaporation nito the atmosphere. D. Riedel Publ. Co., Dortrcht.

Moore, C.J. and Fisch, G., 1986. Estimating heat storage in Amazonian tropical forests. Agric. For. Meteorol., 38: 147-169.

Wright, I.R., Gash, J.H.C., da Rocha, H.R.,Shuttleworth, W.J., Nobre, C.A., Maitelli, G.T., Zamparoni, C.A.G.P. and Carvalho, P.R.A., 1992. Dry season micrometeorology of central Amazonian ranchland. Quart. J. R. Meteorol. Soc., 118: 1083-1099.

Wright, I.R., Manzi, A.O. and da Rocha, H.R., 1995. Surface conductance of Amazonian pasture: model application and calibration for canopy climate. Agric. For. Meteorol., 75: 51-70.

Wright, I.R., Gash, J.H.C.G. and da Rocha, H.R., 1996b. Modelling surface conductance for Amazonian pasture and forest. In Amazon Deforestation and Climate (Eds. J.H.C. Gash, C.A. Nobre, J.M. Roberts and R.L. Victoria), In Press. John Wiley, Chichester. pp 437-458.

Wright, I.R., Nobre, C.A., Tomasella, J, da Rocha, H.R., Roberts, J.M., Vertamatti, E., Culf, A.D., Alval , R.C.S., Hodnett, M.G. and Ubarana, V., 1996b. Towards a GCM surface parameterisation for Amazonia. In Amazon Deforestation and Climate (Eds. J.H.C. Gash, C.A. Nobre, J.M. Roberts and R.L. Victoria), In Press. John Wiley, Chichester. pp 473-504.

Yang, Z.L., Dickinson, R.E. and Shuttleworth, W.J., 1996. Treatment of Soil, Vegetation and Snow in Land-surface Models: A Test of the Biosphere-Atmosphere Transfer Scheme with the HAPEX-MOBILHY, ABRACOS and Russian Data, invited to a BAHC Special Issue of Journal of Hydrology. (in revision)

 

Climate Data from Seven Observation Sites

Bastable, H.G., Shuttleworth, W.J., Dallarosa, R.L.G., Fisch, G. and Nobre C.A. 1993. Observations of climate, albedo and surface radiation over cleared and undisturbed Amazonian forest. Int. J. Climatol. 13,783-796.

Hodnett, M.G., da Silva, L.P., da Rocha, H.R. and Cruz Senna, R.C., 1995. Seasonal soil water storage changes beneath central Amazonian rainforest and pasture. J. Hydrol., 170, 233-254. aitelli, G.T. and Wright, I.R., 1996. On the climate of a river-side city in the Amazon Basin: urban-rural differences in temperature and humidity. In 'Amazon Deforestation and Climate' (Eds. J.H.C.Gash, C.A.Nobre, J.M.Roberts and R.L.Victoria). John Wiley, Chichester, UK. pp 193-206.

McWilliam, A-L.C., Roberts, J.M., Cabral, O.M.R., Leitao, M.V.B.R., de Costa, A.C.L. Maitelli, G.T. and Zamparoni, C.A.G.P., 1993. Leaf area index and above-ground biomass of terra firme rain forest and adjacent clearings in Amazonia. Functional Ecol., 7: 310-317.

McWilliam, A-L.C., Cabral, O.M.R., Gomes, B.M., Esteves, J.L., Roberts, J.M., 1996. Forest and pasture leaf-gas exchange in south-west Amazonia. In 'Amazon Deforestation and Climate' (Eds. J.H.C.Gash, C.A.Nobre, J.M.Roberts and R.L.Victoria). John Wiley, Chichester, UK. pp265-286.

Roberts, J.M., Cabral, O.M.R. & de Aguiar, L.F. 1990. Stomatal and boundary layer conductances measured in a terra firme rain forest. J. Appl. Ecol. 27, 336-353.

Roberts, J.M., Cabral, O.M.R., da Costa, J.P., McWilliam, A-L.C. and Sa, T.D.A, 1996. An overview of the leaf area index and physiological measurements during ABRACOS. In 'Amazon Deforestation and Climate' (Eds. J.H.C.Gash, C.A.Nobre, J.M.Roberts and R.L.Victoria). John Wiley, Chichester, UK. pp287-306.

Sa, T.D.A., Costa, P.C. and Roberts, J.M., 1996. Forest and pasture conductances in southern Par , Amazonia. In 'Amazon Deforestation and Climate' (Eds. J.H.C.Gash, C.A.Nobre, J.M.Roberts and R.L.Victoria). John Wiley, Chichester, UK. pp 241-264.

Salomo, R. de P., 1991. Uso de parcelas permanentes para estudos da vegetaco da floresta tropical umida. 1. Municipio de Maraba, Para. Bol. Mus. Para. Emilio Goeldi, ser. Bot., 7: 543-604.

Shuttleworth, W.J., J.H.C. Gash, C.R. Lloyd, J.M. Roberts, A. de O. Marques, G. Fisch, P. de Silva, M.N.G. Ribeiro, L.C.B. Molion, L.D. de Abreu Sa, C.A. Nobre, O.M.R. Cabral, S.R. Patel and J.C. de Moraes, 1984: Observations of radiation exchange above and below Amazonian forest. Quart. J. Roy. Meteor. Soc., 110,1163-1169.

Wright, I.R., Gash, J.H.C., da Rocha H.R., Shuttleworth, W.J., Nobre, C.A., Maitelli, G.T., Zamparoni, C.A.G.P. & Carvalho, P.R.A. 1992. Dry season micrometeorology of central Amazonian ranchland. Quart. J. Roy. Meterol. Soc. 118, 1083-1099.
 

Forest Carbon Dioxide and Water Vapor Flux

Grace, J., Lloyd, J., McIntyre, J., Miranda, A.C., Meir, P., Miranda, H.S., Moncrieff, J., Massheder, J., Wright, I.R. and Gash, J.H.C., 1995. Fluxes of carbon dioxide and water vapour over an undisturbed tropical rain forest in south-west Amazonia. Global Climate Change, 1: 1-12.

Moncrieff, J.B., Massheder, J.M., Verhoeh, A., Elbers, J., Heusinkveld, B., Scott, S., de Bruin, H., Kabat, P. and Jarvis, P.G., 1995. A system to measure surface fluxes of energy momentum and carbon dioxide. J. Hydrol. In Press.

Wright, I.R., Gash, J.H.C.G., da Rocha, H.R. and Roberts, J.M., 1995. Modelling surface conductance for Amazonian pasture and forest. In Amazon Deforestation and Climate (Eds. J.H.C. Gash, C.A. Nobre, J.M. Roberts and R.L. Victoria), John Wiley,Chichester. pp 437-458.
 

Plant Physiology

McWilliam, A-L.C., Roberts, J.M., Cabral, O.M.R., Leitao, M.V.B.R., de Costa, A.C.L. Maitelli, G.T. and Zamparoni, C.A.G.P., 1993. Leaf area index and above-ground biomass of terra firme rain forest and adjacent clearings in Amazonia. Functional Ecol., 7: 310-317.

McWilliam, A-L.C., Cabral, O.M.R., Gomes, B.M., Esteves, J.L., Roberts, J.M., 1996. Forest and pasture leaf-gas exchange in south-west Amazonia. In 'Amazon Deforestation and Climate' (Eds. J.H.C.Gash, C.A.Nobre, J.M.Roberts and R.L.Victoria). John Wiley, Chichester, UK. pp 265-286.
 

Soil Moisture

Hodnett, M.G., da Silva, L.P., da Rocha, H.R.and Cruz Senna, R.C., 1995. Seasonal soil water storage changes beneath central Amazonian rainforest and pasture. J. Hydrol., 170, 233-254.