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The National Airborne Field Experiment 2005 (NAFE'05) and the Campaign for validating the Operation of Soil Moisture and Ocean Salinity (COSMOS) were undertaken in November 2005 in the Goulburn River catchment, which is located in southeastern Australia. The objective of the joint campaign was to provide simulated Soil Moisture and Ocean Salinity (SMOS) observations using airborne L-band radiometers supported by soil moisture and other relevant ground data for the following: 1) the development of SMOS soil moisture retrieval algorithms; 2) developing approaches for downscaling the low-resolution data from SMOS; and 3) testing its assimilation into land surface models for root zone soil moisture retrieval. This paper describes the NAFE'05 and COSMOS airborne data sets together with the ground data collected in support of both aircraft campaigns. The airborne L-band acquisitions included 40 km x 40 km coverage flights at 500-m and 1-km resolution for the simulation of a SMOS pixel, multiresolution flights with ground resolution ranging from 1 km to 62.5 m, multiangle observations, and specific flights that targeted the vegetation dew and sun glint effect on L-band soil moisture retrieval. The L-band data were accompanied by airborne thermal infrared and optical measurements. The ground data consisted of continuous soil moisture profile measurements at 18 monitoring sites throughout the 40 km x 40 km study area and extensive spatial near-surface soil moisture measurements concurrent with airborne monitoring. Additionally, data were collected on rock coverage and temperature, surface roughness, skin and soil temperatures, dew amount, and vegetation water content and biomass. These data are available at www.nafe.unimelb.edu.au. Index Terms--Microwave radiometry, National Airborne Field Experiment (NAFE), passive microwave, soil moisture, Soil Moisture and Ocean Salinity (SMOS).

In the absence of direct erosion measurements, the soil activity of the fallout radionuclide caesium-137 ([sup.137]Cs) offers an attractive tool for the estimation of long-term (approximately 45 years) net surface and minor rill soil erosion rates for hillslopes. A transect-based soil sampling technique was applied to one woodland and five grazed pasture hillslopes in the Williams River water-supply catchment in the Hunter Valley, New South Wales. An Australian regression model (SOILOSS) relating net soil loss from runoff-erosion plots to [sup.137]Cs deficit in soils was used to calculate a weighted net surface and minor rill erosion rate for the six hillslopes. The net median surface erosion rates ranged between 0.00 and 0.64 t [ha.sup.-1] [yr.sup.-1] with the average median soil erosion rate of 0.19 t [ha.sup.-1] [yr.sup.-1] (std. dev. = 0.23), indicating that these hillslopes were unlikely to be major sources of sediment to the catchment's waterways. Net soil loss rates were also shown to be low in comparison to Australia-wide data and comparable to hillslope data obtained elsewhere in the same region. Minimum and maximum error bounds were provided with each erosion rate to account for radionuclide detector count error. For one hillslope the estimated error due to detection was 1.34 t [ha.sup.-1] [yr.sup.-1], while the remaining five hillslopes exhibited error of up to 0.41 t [ha.sup.-1] [yr.sup.-1]. Correlation analyses between the net soil loss rates and physical hillslope characteristics were non-significant. KEY WORDS Soil erosion; caesium-137; hillslopes; SOILOSS; sediment tracing; Reduced Major Axis (RMA) analysis

Apart from early studies by Griffith Taylor, very little work has been carried out to describe the variety of thermal environments experienced by man in Australia. Previous studies are reviewed and new models are developed to quantify energy exchanges at specific times of the year within a continuum of possible responses to maintain homeothermy. Maps are presented of cold and heat stress to naked man, of work rates to achieve neutrality, and of clothing insulation requirements. Estimates are also made of primary energy inputs necessary to reach comfortable indoor temperatures by space heating and cooling within standard housing. It is further suggested that the success of settlement is associated with the relevance of human responses to the thermal environment. [ABSTRACT FROM AUTHOR]