An operational satellite remote sensing system for ocean fishery

Ocean environmental information is very important to supporting the fishermen in fishing and satellite remote sensing technology can provide it in large scale and in near real-time. Ocean fishery locations are always far away beyond the coverage of the satellite data received by a land-based satellite receiving station. A nice idea is to install the satellite ground station on a fishing boat. When the boat moves to a fishery location, the station can receive the satellite data to cover the fishery areas. One satellite remote sensing system was once installed in a fishing boat and served fishing in the North Pacific fishery areas when the boat stayed there. The system can provide some oceanic environmental charts such as sea surface temperature (SST) and relevant derived products which are in most popular use in fishery industry. The accuracy of SST is the most important and affects the performance of the operational system, which is found to be dissatisfactory. Many factors affect the accuracy of SST and it is difficult to increase the accuracy by SST retrieval algorithms and clouds detection technology. A new technology of temperature error control is developed to detect the abnormity of satellite-measured SST. The performance of the technology is evaluated to change the temperature bias from -3.04 to 0.05 ℃ and the root mean square (RMS) from 5.71 to 1.75℃. It is suitable for employing in an operational satellite-measured SST system and improves the performance of the system in fishery applications. The system has been running for 3 a and proved to be very useful in fishing. It can help to locate the candidates of the fishery areas and monitor the typhoon which is very dangerous to the safety of fishing boats.

Data processing and error analysis for the CE-1 Lunar microwave radiometer

The microwave radiometer （MRM） onboard the Chang＇ E-1 （CE-I） lu- nar orbiter is a 4-frequency microwave radiometer, and it is mainly used to obtain the brightness temperature （TB） of the lunar surface, from which the thickness, temperature, dielectric constant and other related properties of the lunar regolith can be derived. The working mode of the CE-1 MRM, the ground calibration （including the official calibration coefficients）, as well as the acquisition and processing of the raw data are introduced. Our data analysis shows that TB increases with increasing frequency, decreases towards the lunar poles and is significantly affected by solar illumination. Our analysis also reveals that the main uncertainty in TB comes from ground calibration.

Effect of Thermal Radiation Heat Transfer on the Temperature Measurement by the Thermocouple in Premixed Laminar Flames

In the past 30 years,the effect of thermal radiation and convection heat transfer,which are predominant at high temperature and can affect the measurement accuracy of thermocouple,were not fully considered in the field of laminar flame researches.In this work,the effect of thermal radiation heat transfer was newly calculated by determining the spectral irradiation heat flux from the whole space to thermocouple and the radiation heat loss from thermocouple junction to surroundings.Analysis reveals that the thermocouple itself maintains at high temperature,resulting serious thermal radiation heat loss,which can be compensated via receiving energy from convection-transferred heat as well as thermal radiation emitted by flame and burner surface.Such method was applied to correct the temperatures measured by thermocouple in rich nitromethane flame as reference.The results indicate that the radiation heat loss plays a dominant role,while the radiations emitted by flame and burner surface account for minor contribution with the percentage of 20.78%at the height above burner(HAB)of 0.4 mm,3.63%at HAB of 2.0 mm and even smaller at higher HAB.Temperature correction states that the maximum temperature error is 117.60 K,where the effect of thermal radiation emitted by flame and burner surface is less than 1.75 K.Consequently,it is provably reasonable and feasible to concentrate on the radiation heat loss and ignore the effect of thermal radiation emitted by flame and burner in real combustion processes.

Aerosol as a critical factor causing forecast biases of air temperature in global numerical weather prediction models

Weather prediction is essential to the daily life of human beings. Current numerical weather prediction models such as the Global Forecast System(GFS) are still subject to substantial forecast biases and rarely consider the impact of atmospheric aerosol, despite the consensus that aerosol is one of the most important sources of uncertainty in the climate system. Here we demonstrate that atmospheric aerosol is one of the important drivers biasing daily temperature prediction. By comparing observations and the GFS prediction, we find that the monthly-averaged bias in the 24-h temperature forecast varies between ± 1.5 ℃ in regions influenced by atmospheric aerosol. The biases depend on the properties of aerosol, the underlying land surface, and aerosol–cloud interactions over oceans. It is also revealed that forecast errors are rapidly magnified over time in regions featuring high aerosol loadings. Our study provides direct ‘‘observational" evidence of aerosol’s impacts on daily weather forecast, and bridges the gaps between the weather forecast and climate science regarding the understanding of the impact of atmospheric aerosol.