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.

The micrometeorology disk files are as follows:
PASTURE (compressed into PAST.EXE)

FOREST (compressed into FORST.EXE)

where the site codes are as follows,

Site details are given in the climate text file AB-AWS.TXT

Within each file each datum is in free format, in seven character columns and space delineated. Missing data are indicated by a value of -99. In summary the columns are follows:

DATA FILE DETAILS AND NOTES

The following is a more detailed description of each column giving:

Instrument type details (AWS refers to the collocated Automatic Weather Station)
Instrument location details
Derivation of analyzed figures
Quality control information
Cautionary notes where problems arise

General information concerning groups of missions is given first, followed by notes specific to individual missions indicated by the site code and mission number (e.g. FD-2)

1. JULIAN DAY NUMBER
All data files contain a continuous time series of hourly information, although some files have gaps in individual channels.

2. HOUR
Time is local and gives the end time of the hourly period for which the total or average is given.

3. TOTAL INCOMING SHORT-WAVE (W/m^2)
AWS - Recorded by Kipp and Zonen solarimeter

4. REFLECTED SHORT-WAVE (W/m^2)
AWS - Recorded by Kipp and Zonen solarimeter

5. NET RADIATION (W/m^2)
AWS - REBS net all-wave radiometer

6. SOIL HEAT FLUX (W/m^2)
This is a larger and more important component of the energy balance at pasture sites than forest. Each AWS has two sensors placed at 5mm in the soil which is an adequate sample for forests but less so for pasture. During most pasture missions 9 sensors were used at 5mm depth. Some gaps have been filled using regressions against either net radiation in the pasture or air temperature in the forests.

NS-3 During the dry start to this mission evaporation could be occurring below the sensors creating a small underestimation in the heat or vapour flux. Compensation for this could be derived from the following years analysis. (see below)

NS-45 During the driest part of this mission evaporation below the shallow sensors was identified. The evaporation front passed below the 5mm sensors on about day 271. After this SHF in the data base is derived from the deeper sensors (15cm) to give the overall heat energy leaving the system, and diurnally adjusted for soil heat storage above the sensors using the soil temperature measurement.

BS-6 Record based upon only two sensors.

BS-6 10% patched using regression with net radiation

RJ-3 ## GAP ## 8 days (266-234) filled by regression with air temperature

7. AIR TEMPERATURE (oC)
AWS - Platinum resistance thermometer except FD-M1, FD-M2 and other instances where it was necessary to the micromet. channel.

8. SPECIFIC HUMIDITY (g/kg)
AWS - Platinum resistance wet-bulb thermometer except FD-M1, FD-M2 and other instances where it was necessary to the micromet. channel.

9. WIND SPEED (m/s)
AWS - Didcot Instruments, UK

10. WIND DIRECTION (degrees arc, clock-wise from North)
AWS - Didcot Instruments, UK

11-15. MOMENTUM FLUX VARIABLES
Friction velocity (m/s)
Stability parameter, z/L
Integrated stability correction for sensible heat flux
Integrated stability correction for momentum flux
Aerodynamic conductance for heat fluxes (mm/s)

All momentum flux and stability variables are calculated using the best possible roughness calibration for each site (see Wright et al 1992, Wright et al 1996b) as follows:

Data base columns 11-14 where then calculated by iteration of the wind profile and stability correction formulae based on the Monin-Obukhov length, L, and similarity theory (Arya 1988). The aerodynamic conductance given in column 15 is then calculated from the friction velocity and stability corrections, and is the conductance applicable for heat and water vapour. This application includes a correction for the different source/sink heights for heat and momentum and gives ln(z0m/z0h) the value 2.0 for pasture and 1.5 for forest (Brutsaert, 1984). When heat flux data is missing the variables are given for neutral conditions

16. BULK SURFACE CONDUCTANCE (mm/s)
Calculated from a rearrangement of the Penman-Monteith equation. The value is set to -99 either at night or when the calculated values is very high or negative. (Wright et al. 1995,1996a)

17. LATENT HEAT FLUX (W/m^2)
Pasture and forest fluxes were frequently verified against other independent Bowen ratio and eddy-correlation devices

Pasture - evaporation calculated from estimates of Bowen ratio (9m profile tower), directly from an eddy-correlation device or as a residual of the energy balance when the two former sources are unavailable. A few gaps of not more than 2 daylight hours were filled using a detailed time-series model of Bowen ratio.

Forest - the same as for pasture but without the use of psychrometer profiles. Changes in biomass heat storage were include in the residual energy balance method (Moore and Fisch,1986)

18. SENSIBLE HEAT FLUX (W/m^2)
Pasture and forest fluxes were frequently verified against other independent Bowen ration and eddy-correlation devices

Pasture - heat flux calculated from estimates of Bowen ratio (9m profile tower), directly from an eddy-correlation device. A few gaps of not more than 2 daylight hours were filled using a detailed time-series model of Bowen ratio.

Forest - the same as for pasture but without the use of psychrometer profiles.

19. EITHER PASTURE: SOIL MOISTURE IN THE ROOT ZONE (m3/m^3)
Mean moisture storage in the top 1.5 m (FD) or 2.0 m (NS & BS) of soil, derived from between 5 and 8 neutron access tubes with 10-20 cm measurement depth increments. (Wright 1995, 1996a)
Or FOREST: CHANGE IN BIOMASS HEAT STORAGE (W/m^2)
Calculated using the AWS air temperature and humidity in the equations of Moore and Fisch (1986) and best estimates of forest structure parameters from Reserva Jaru.

20. RAINFALL (mm)
AWS - Didcot Instruments, UK. 0.1-0.2mm tipping bucket device.

A Manual raingauge showed little significant rain fall up to day 277, except for 27mm during the afternoon of day 270.

21-23. SOIL TEMPERATURE AT 10cm (pasture only) (oC)
SOIL TEMPERATURE AT 20cm (pasture only)(oC)
SOIL TEMPERATURE AT 40cm (pasture only)(oC)
Mean of three thermistors at 10 cm and a single thermistor at the other two depths.

REFERENCES

Arya, S.P., 1988. Introduction to micrometeorology. Academic Press (London). pp 307.

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).