| Based on the Anqing City weather stations60a (a represent year) continuous meteorological observation data, the use of mathematical statistical analysis software SPSS and fortran compiler is linear number of temperature, precipitation, sunshine and evaporation amount of certain meteorological factors of spatial and temporal changes in character is tics regression analysis the correlation test and morlet continuous wavelet transform analysis, to study the temporal and spatial variations in the60a trends and cycles and cycle shocks to predict short-term future climate change trends in Anqing City. The following conclusions:(1) The annual precipitation in Anqing City in nearly60years was weak increasing trend. Rainfall mainly concentrated in the spring and summer, the spring precipitation was struck downward trend, summer and winter was struck upward trend in autumn downward trend is not obvious. From the the the60years precipitation cyclical point of view, from the the between1952-2010and years experienced a total of6times of probability of wet and dry alternately, starting in2010Anqing will enter the the next the wet period. Large-scale periodic around16a, mesoscale cycle in6-8a about small-scale periodic2-3a around, and the large-scale periodic global.During the spring and summer Anqing influenced by the monsoon circulation, frequent atmospheric circulation interannual variability of precipitation variability, Wet and Dry alternately frequent, small-scale periodic shocks significant inter-annual variation of precipitation mutation points, the frequency of droughts and floods is high. Autumn and winter by the westerlies, the prevailing northerly airstream, the partial dry air over the spring and summer, precipitation variability, inter-annual variation of precipitation is relatively small, alternating droughts and floods more slowly than the spring and summer, the small-scale periodic shocks was not significant. Rainfall concentrated in spring and summer, respectively, accounting for33.75%and41.16%of the annual precipitation, annual precipitation cycle by the spring and summer precipitation cycle. Overall, Anqing past60years, small-scale periodic shocks significantly, periodic, inter-annual variation of precipitation, precipitation drought and flood alternately changes frequently prone to floods and drought, but a low probability of severe drought. (2) nearly60years the Anqing City as a whole in a warming trend, the overall trend consistent with global warming, Anqing in a relatively cool period before1993, after1993, Anqing City, the temperature sharply warming and in2007reached the highest value in1993, an important point of abrupt climate change in the history of Anqing. the temperature change in the history of the main16a and32a of the two large-scale periodic its periodic oscillation stable, high continuity, the periodic oscillation time scale covering a wide are globally.16a and32a-scale periodic shocks trend can be predicted, Anqing City in about2010After experiencing will be the last warm period into a colder cycle, the cycle duration is about8-16years. And small-scale periodic2-3a,6A about small-scale cycles, small-scale periodic coverage is smaller, does not have a global, but its cycle shock strength, cyclical changes in inter-annual temperature is easy dramatic changes, likely to cause high and low temperatures disasters, an adverse impact on agricultural production, transportation and power transmission. Large-scale periodic trend appeared in a macro on a large scale and well-being of small-scale cycles show abnormal changes in temperature, with the precise positioning of the role of micro precision.(3) The sunshine hours in the past60years has been in a significant downward trend in the mid-sixties to the mid-eighties, the downward trend since the start of the eighties, the downward trend slowed, nearly60years of sunshine hours is decreasing, mainly due to the decrease in summer sunshine hours.The Sunshine hours of annually changing and the changing in seasons there are large-scale32a cycle, mesoscale8a and small-scale periodic2-3a, large-scale periodic globally stable periodic oscillation, small and medium-scale cycle does not have a domain-wide. Small and medium-scale cycle of seasons than the large-scale periodic shocks center signal cycle severe shock, shock intensity, periodic cycle significantly. Cycle of annual sunshine hours, the large-scale periodic small-scale periodic oscillation strength and size of the cyclical changes in the basic consistent with the periodic oscillation strength, periodic changes. Fitting The trend predicted that the current low cycle sunshine hours is not over the next few years the number of hours of sunshine in Anqing also at a low period in accordance with the contour of the cycle.(4)60years Anqing evaporation in a decreasing trend, not significant trend, the amount of years and seasons evaporation cycle changes similar, are presence of large-scale periodic32a and the small-scale periodic2-3a, large-scale cycles have both globally small-scale cycle, though not with the global monitoring, but its periodic oscillation strength, cyclical changes in the most obvious. The large-scale cycle has a certain predictability, small-scale cycle having a more accurate positioning.32a cycle on behalf of the domain-wide large-scale periodic change projections, until2011, the last cycle is not over, Anqing City in the evaporation relatively high value of the cycle, in recent years in the future, Anqing City will remain relatively large period of evaporation.(5) Anqing City nearly60years the average annual drought index was1.19, slightly larger than1, the Anqing climate is relatively warm environment, spring drought index of0.9is less than1. Fall of2.7greater than1, the income is greater than the expenditure of the spring water, in a wet environment. Fall in semi-arid state, Anqing belongs to the north subtropical monsoon climate, affected by the East Asian monsoon precipitation in the spring, the average low temperature evaporation weak, moist climate. Fall prevailing westerly winds, less rainfall, high pressure, strong evaporation, dry climate, drought prone. Annual and seasonal cycle of large-scale periodic32a and20a and the small-scale periodic2-3A, the basic law of large-scale periodic domain-wide, but the shock strength is less than the small-scale periodic small-scale periodic does not have any globally, in different years interval cycle shock, but the shock strength, cyclical changes in the large-scale periodic obvious.(6) Evaporation and precipitation was negatively correlated, and the strong correlation of evaporation temperature and sunshine were positively correlated. That is, the higher the temperature, the longer sunshine hours, evaporation is more intense. Drought index and evaporation, temperature, and sunlight showed a positive correlation, a strong correlation, evaporation, temperature and sunlight will cause the underlying surface moisture loss strengthen. Drought index and precipitation was negatively related to increased precipitation, moisture increased revenue, reduced drought index. The relationship between temperature and precipitation negative correlation, precipitation as temperatures rise gradually reduced due to the development of the trend toward global climate warming, precipitation will be gradually reduced, prone to drought, the need for further preventive measures. |
