Lunar regolith parameters, such as physical temperature, thickness and dielectric constant, are important in studying regolith features, distribution of lunar resources and evolution of the Moon. There had been no measurement obtained by lunar-orbit-borne microwave radiometer applied to evaluate the properties of lunar regolith before CE-1 Lunar Microwave Sounder (CELMS) being launched. CEMLS is the first passive microwave radiometer in the world to sound the surface of the Moon. The brightness temperatures (T B ) sensed by CELMS include complicated information on the above geophysical parameters. In this paper, algorithms of retrieving dielectric constant, regolith thickness, and 3 He content from CELMS brightness temperatures are developed, and the results are compared with those from literature. The results show that the regolith thicknesses are mostly in the range of 4.0-6.0 m, and 43% of them are bigger than 5.0 m. The content of 3 He evaluated by retrieved regolith thickness is about 1.03 million tons. CE-1 Lunar Microwave Sounder (CELMS), lunar regolith, dielectric constant, lunar regolith thickness, 3 He, retrieval Citation:Wang Z Z, Li Y, Jiang J S, et al. Lunar surface dielectric constant, regolith thickness, and 3 He abundance distributions retrieved from the microwave brightness temperatures of

Reanalysis projects and satellite data analysis have provided surface wind over the global ocean. To assess how well one can reconstruct the variations of surface wind in the data-sparse Southern Ocean, sea surface wind speed data from 1) the National Centers for Environmental Prediction-Department of Energy reanalysis (NCEP-DOE), 2) the European Centre for Medium-Range Weather Forecasts (ECMWF) Interim Re-Analysis (ERA-Interim), 3) National Climate Data Center (NCDC) blended sea winds, and 4) crosscalibrated multiplatform (CCMP) ocean surface velocity are evaluated. First, the accuracy of sea surface wind speed is validated with quality-controlled in situ measurements from research vessels. The results show that the CCMP value is closer to the ship observations than other products, whereas the NCEP-DOE value has the largest systematic positive bias. All four products show large positive biases under weak wind regimes, good agreement with the ship observations under moderate wind regimes, and large negative biases under high wind regimes. Second, the consistency and discrepancy of sea surface wind speed across different products is examined. The intercomparisons suggest that these products show encouraging agreement in the spatial distribution of the annual-mean sea surface wind speed. The largest across-data scatter is found in the central Indian sector of the Antarctic Circumpolar Current, which is comparable to its respective interannual variability. The monthly-mean correlations between pairs of products are high. However, differing from the decadal trends of NCEP-DOE, NCDC, and CCMP that show an increase of sea surface wind speed in the Antarctic Circumpolar region, ERA-Interim has an opposite sign there.

CE-1 Lunar Microwave Sounder (CELMS) is the first passive microwave radiometer in the world to sound the surface of the Moon in the lunar orbit at altitude of 200 km. The scientific objective of CELMS is to obtain global brightness temperature (T B ) of the Moon, to retrieve information on lunar regolith, and to evaluate the distribution of helium-3 on the Moon implanted by solar wind. Before launch of CELMS, a series of experiments were carried out in laboratories to test the performances of the systems, and to calibrate the responses between the input of T B and the output of voltage from the receivers. However, the thermal condition exposed to CELMS is more complicated in lunar orbit than on the Earth, which makes the temperatures of different parts of CELMS wave vary greatly, and the cosmic background is not very clean due to the pointing of cold space antenna to the direction of the satellite running, which brings uncertainties into data-processing of CELMS when the temperature of cold space is used as a calibrator. Furthermore, the lack of knowledge on the lunar ingredients and compositions, distributions of physical temperatures, and properties on lunar microwave radiation leads to difficulties in validating the measurements and retrievals of CELMS. By analyzing the results of ground experiments and the measurements of CELMS in-orbit, along with our knowledge of the properties of lunar surface, here we give algorithms on calibration and antenna pattern correction (APC) of CELMS. We also describe in detail the principle of microwave transfer among the elements of CELMS, and discuss the method on testing calibration parameters of the system. In addition, the theory and model on correction antenna pattern of CELMS are developed by comparing antenna temperatures by CELMS with those simulated by microwave radiative transfer models. The global distribution of T B is given and the features of T B are analyzed. Our results show rich information included in T B on the properties of lunar regolith, especially the thickness and dielectric constant, which are nearly directly reflected by the differences of T B at day and those at night.

In comparison with the ECMWF data, some obviously positive differences exist at high southern latitudes in January and at high northern latitudes in July.

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Surface temperature profile is an important parameter in lunar microwave remote sensing. Based on the analysis of physical properties of the lunar samples brought back by the Apollo and Luna missions, we modeled temporal and spatial variation of lunar surface temperature with the heat conduction equation, and produced temperature distribution in top 6.0 m of lunar regolith of the whole Moon surface. Our simulation results show that the profile of lunar surface temperature varies mainly within the top 20 cm, except at the lunar polar regions where the changes can reach to about 1.0 m depth. The temperature is stable beyond that depth. The variations of lunar surface temperature lead to main changes in brightness temperature (T B ) at different channels of the lunar microwave sounder (CELMS) on Chang'E-1 (CE-1). The results of this paper show that the temperature profile influenced CELMS T B , which provides strong validation on the CELMS data, and lays a solid basis for future interpretation and utilization of the CELMS data. CE-1 lunar Microwave Sounder (CELMS), lunar surface temperature, lunar surface temperature profile, heat conduction equation, simulation of brightness temperature Citation:Li Y, Wang Z Z, Jiang J S. Simulations on the influence of lunar surface temperature profiles on CE-1 lunar microwave sounder brightness temperature.CE-1 lunar Microwave Sounder (CELMS) is a main payload of Chang'E-1 Moon orbit satellite, which is used to obtain brightness temperatures of lunar surface and then retrieve thickness of lunar regolith. The microwave radiation of lunar regolith is consisted of brightness temperature contribution from all layers under the surface. The probing depth of CELMS depends on frequency. The physical characteristics of lunar regolith at different depth, such as temperature, dielectric constant, density, thermal conductivity and specific heat, etc., are different. So are the emissivity, transmissivity, and physical temperature of different layers.In addition, the rates that different layers' radiation brightness temperatures reach the surface are different. Thus, by analyzing T B obtained by CELMS, we can retrieve the depth where the radiation came from and then retrieve the physical characteristics of lunar regolith in that depth. The influences of these physical parameters on T B received by CELMS are different, and the parameters are the scientific objectives of CELMS, therefore, it is necessary to analyze the relationship among them and study the mechanism that leads to the influences. This paper focuses on the influence of different lunar temperature at different regolith layer on microwave brightness temperature. The Sun is the sole source of energy for lunar surface temperature. Since there is no atmosphere on lunar surface, lunar surface temperature changes dramatically following rising and setting of the Sun. Because

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