Abstract: We began to put fuzzy mathematics into use in forecasting since 1982, and then the statistical forecasting was made by using the NWP products with the theory and. method of fuzzy sets. In this paper, we describe the information on this aspect.
Abstract: The non-balance wind (difference between real and balance winds) is decomposed, into divergent and rotational components. The dynamical impacts of these two components on the development of heavy rainstorm are analysed. It is found that the rotational part plays a role in maintenance of the divergent field.Three experiments with differential initialization methods are carried out by using a 5 level limited area model. The precipitation forecast is improved if both the divergent and rotational components are included in the initial wind field.
Abstract: An extensive very heavy rain fell over the Huaihe River on August 23 and 24, 1980. It is pointed in this paper that due to the large-scale tropical SW-S-SE monsoon current confluent zone from the Bay of Bengal-South China Sea-NW Pacific, to its north, at the downstream of the confluent point, a South China vortex was introduecd and developed with 7-8 spiral cloud belts. The SW jet stream on lower level intensified and propagated eastward. It not only induced an energy frontal zone between Yangtze and Huaihe Rivers, but also steered the South China vortex moving eastward. At last, a very heavy rain occurred in the warm sector to the southside of the vortex, just over the Huaihe River.
Abstract: According to the data of solar direct radiation observation at the Yunling Bai-mang Snow Mountain in the cenTRal part of the Hengduan Mountain Range in 1983 and 1984,the Linke atmosphere turbidity coefficient TP was calculated and analysed. It's found that TP decreases with the increase of altitude. The annual variations of TP show similar TRend at different altitude.TP is maximum in July and August, and TP is Minimum in November. TP may he divided into the aerosol turbidity coefficient TR and the vapour turbidity coefficient TW, The annual variation of TW is in accordance with the annual disTRibution of the precipitation, and TR shows the opposite variation tendency.
Abstract: A method of estimating the outgoing longwave flux on. cirrus clouds is described. First geomeTRy mark model is set, and the scattered of cirrus clouds water content in vertical direction is assumed. Second the models are approximately simplified model gets the outgoing longwave flux on cirrus clouds.Both the results and satellite sounding data approximately reach the same results. The relations between the thickness of cloud and the outgoing longwave flux and the height form ground to the base of cloud and the outgoing longwave flux are respective.
Abstract: In this paper, logarithmic normal distribution is used to calculate annual maximum wind speed. Main differences of this method from others are that there is a more perfect subsample inspection and the upper limit of tolerance can be calcula-ted.