The seasonal cycle of the climate of 9000 years before present was simulated with the IAP two-level atmospheric general circulation model. The incoming solar radiation was specified from the orbital parameters for 900...The seasonal cycle of the climate of 9000 years before present was simulated with the IAP two-level atmospheric general circulation model. The incoming solar radiation was specified from the orbital parameters for 9000 years ago. The boundary conditions of that time were prescribed to the present value because of the small differences between the two. The change in radiation makes temperature to be higher in summer and lower in winter over large areas of the land; and the increased temperature contrast between the land and the ocean strengthens the summer monsoon circulation and increases the precipitation over there. The asymmetry of temperature change between the Northern Hemisphere and the Southern Hemisphere and between summer and winter still exists, which agrees with that get from the previous perpetual experiments.展开更多
It is possible to conclude that typical course of graph which analyse course of germinability during the year at every cultivar is observable. Germination usually shows a minimum in December, but mainly in January and...It is possible to conclude that typical course of graph which analyse course of germinability during the year at every cultivar is observable. Germination usually shows a minimum in December, but mainly in January and in February. Maximum of germinability is observed in the spring and summer time. This phenomenon isn’t result of the dormancy or secondary dormancy because during of long term seed storage, germinability has similar curve every year, only number of germinative seeds stepwise decrease every year at every month of storage. Every species or cultivar of crops has a typical course of the germinability during the year. There are also species (crops), that have germination process during the year almost constant i.e., without variation during the year, but it is a minority of genotypes, rather exceptions. The annual course of germination is nearly identical to the annual course of the magnetic declination. From the theoretical practical view, there is possibility (but not certainty!) that in case of testing the seed germination at begin or end of year at genotypes with large variability of germinability during the year, that this phenomenon have negative impact on seed certification by companies producing seeds for cultivation practice in some species.展开更多
This paper presents a statistical scheme for the seasonal forecasting of North China's surface air temperature (NCSAT) during winter. Firstly, a prediction model for an decrease or increase of winter NCSAT is esta...This paper presents a statistical scheme for the seasonal forecasting of North China's surface air temperature (NCSAT) during winter. Firstly, a prediction model for an decrease or increase of winter NCSAT is established, whose predictors are available for no later than the previous September, as this is the most favorable month for seasonal forecasting up to two months ahead.The predicted NCSAT is then derived as the sum of the predicted increment of NCSAT and the previous NCSAT. The scheme successfully predicts the interannual and the decadal variability of NCSAT. Additionally, the advantages of the prediction scheme are discussed.展开更多
Reanalysis data from NCEP/NCAR are used to systematically study preceding signals of monthly precipitation anomalies in the early raining season of Guangdong province, from the viewpoints of 500-hPa geopotential heigh...Reanalysis data from NCEP/NCAR are used to systematically study preceding signals of monthly precipitation anomalies in the early raining season of Guangdong province, from the viewpoints of 500-hPa geopotential height field, outgoing longwave radiation (OLR) field, sea surface temperature (SST) and fourteen indexes of general circulation depicting atmosphere activity at high, middle and low latitutes. Being multiple tools of information, a number of conceptual models are formulated that are useful for prediction of the magnitude of monthly precipitation (drought, flood and normal conditionss).展开更多
文摘The seasonal cycle of the climate of 9000 years before present was simulated with the IAP two-level atmospheric general circulation model. The incoming solar radiation was specified from the orbital parameters for 9000 years ago. The boundary conditions of that time were prescribed to the present value because of the small differences between the two. The change in radiation makes temperature to be higher in summer and lower in winter over large areas of the land; and the increased temperature contrast between the land and the ocean strengthens the summer monsoon circulation and increases the precipitation over there. The asymmetry of temperature change between the Northern Hemisphere and the Southern Hemisphere and between summer and winter still exists, which agrees with that get from the previous perpetual experiments.
文摘It is possible to conclude that typical course of graph which analyse course of germinability during the year at every cultivar is observable. Germination usually shows a minimum in December, but mainly in January and in February. Maximum of germinability is observed in the spring and summer time. This phenomenon isn’t result of the dormancy or secondary dormancy because during of long term seed storage, germinability has similar curve every year, only number of germinative seeds stepwise decrease every year at every month of storage. Every species or cultivar of crops has a typical course of the germinability during the year. There are also species (crops), that have germination process during the year almost constant i.e., without variation during the year, but it is a minority of genotypes, rather exceptions. The annual course of germination is nearly identical to the annual course of the magnetic declination. From the theoretical practical view, there is possibility (but not certainty!) that in case of testing the seed germination at begin or end of year at genotypes with large variability of germinability during the year, that this phenomenon have negative impact on seed certification by companies producing seeds for cultivation practice in some species.
基金jointly supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.KZCX2-YW-QN202)the National Basic Research Program of China(Grant Nos.2010CB9503042 and 2009CB421406)strategic technological program of the Chinese Academy of Sciences(Grant No.XDA05090426)
文摘This paper presents a statistical scheme for the seasonal forecasting of North China's surface air temperature (NCSAT) during winter. Firstly, a prediction model for an decrease or increase of winter NCSAT is established, whose predictors are available for no later than the previous September, as this is the most favorable month for seasonal forecasting up to two months ahead.The predicted NCSAT is then derived as the sum of the predicted increment of NCSAT and the previous NCSAT. The scheme successfully predicts the interannual and the decadal variability of NCSAT. Additionally, the advantages of the prediction scheme are discussed.
基金Short-term Climate Prediction Study for Guangdong Province a key project of Guangdong Science and Technology Committee in the national 9th five-year economic development plan Research on Long-term Tendency Prediction System for Floods/Drought and Typh
文摘Reanalysis data from NCEP/NCAR are used to systematically study preceding signals of monthly precipitation anomalies in the early raining season of Guangdong province, from the viewpoints of 500-hPa geopotential height field, outgoing longwave radiation (OLR) field, sea surface temperature (SST) and fourteen indexes of general circulation depicting atmosphere activity at high, middle and low latitutes. Being multiple tools of information, a number of conceptual models are formulated that are useful for prediction of the magnitude of monthly precipitation (drought, flood and normal conditionss).
基金supported by the National Natural Sciences Foundation of China[41375112],[41530426],[41575058]the Key Technology Talent Program of the Chinese Academy of Sciencesthe Public Science and Technology Research Funds Projects of Ocean[201505013]
