The observation data from ground surface meteorological stations is an important basis on which climate change research is carried out, while the homogenization of the data is necessary for improving the quality and h...The observation data from ground surface meteorological stations is an important basis on which climate change research is carried out, while the homogenization of the data is necessary for improving the quality and homogeneity of the time series. This paper reviews recent advances in the techniques of identifying and adjusting inhomogeneity in climate series. We briefly introduce the results of applying two commonly accepted and well-developed methods (RHtest and MASH) to surface climate observations such as temperature and wind speed in China. We then summarize current progress and problems in this field, and propose ideas for future studies in China. Along with collecting more detailed metadata, more research on homogenization technology should be done in the future. On the basis of comparing and evaluating advantages and disadvantages of different homogenization methods, the homogenized climate data series of the last hundred years should be rebuilt.展开更多
Monthly temperature and precipitation time-series for the Zhujiang River Basin are analyzed in order to identify changes in climate extremes. Daily temperature and precipitation data from 1961 to 2007 of 192 meteorolo...Monthly temperature and precipitation time-series for the Zhujiang River Basin are analyzed in order to identify changes in climate extremes. Daily temperature and precipitation data from 1961 to 2007 of 192 meteorological stations are used. Two temperature indicators (monthly mean and monthly maximum mean) and three precipitation indicators (monthly total, monthly maximum consecutive 5-day precipitation, and monthly dry days) are analyzed. Tendencies in all five indicators can be observed. Many stations show significant positive trends (above the 90% confidence level) for monthly mean temperatures and monthly maximum mean temperatures. For all months, a significant increase in temperature from 1961 to 2007 can be observed in the entire basin with the coastal area in particular. Positive trends of precipitation extremes can be observed from January to March. Negative trends are detected from September to November. The number of dry days in October increased significantly at 40% of all meteorological stations. Stations with changes of monthly precipitation extremes are scattered over the Zhujiang River Basin. An aggregation of heat waves and droughts can be detected which is accompanied by significant increases of temperature extremes and the negative tendencies in precipitation extremes. The detection of tendencies in climate station density. extremes essentially relies on a good data quality and high展开更多
The task of climate observation data processing is central to the quality of an assessment of future climate change impact. The current state-of-the-art is based on the long-running observation records of the meteorol...The task of climate observation data processing is central to the quality of an assessment of future climate change impact. The current state-of-the-art is based on the long-running observation records of the meteorological stations. However, it is common for the developing states to have only relatively short and/or intermittent record histories. The issue becomes even more aggravated under an effort to assess the climatic trends for specific territories with few meteorological stations. The paper offers a simple and effective technique to handle the climate observations; the technique makes the most complete use of an available data set by counting the data provided by all meteorological stations including those with short records and omissions. The method is based on numeric differentiation of source data samples.展开更多
Enhanced observational meteorological elements,energy fluxes,and the concentration of dust aerosols collected from the Semi-Arid Climate Observatory and Laboratory(SACOL) during a typical dust storm period in March 20...Enhanced observational meteorological elements,energy fluxes,and the concentration of dust aerosols collected from the Semi-Arid Climate Observatory and Laboratory(SACOL) during a typical dust storm period in March 2010 at Lanzhou were used in this paper to investigate the impact of dust aerosols on near surface atmospheric variables and energy budgets.The results show that the entire dust storm event was associated with high wind velocities and decreasing air pressure,and the air changed from cold and wet to warm and dry and then recovered to its initial state.The response of energy fluxes occurred behind meteorological elements.At high dust concentration periods,the net radiation was significantly less in the daytime and higher at night,while the heat fluxes displayed the same trend,indicating the weakening of the land-atmosphere energy exchange.The results can be used to provide verification for numerical model results in semi-arid areas.展开更多
A nested-model system is constructed by embedding the regional climate model RegCM3 into a general circulation model for monthly-scale regional climate forecast over East China. The systematic errors are formulated fo...A nested-model system is constructed by embedding the regional climate model RegCM3 into a general circulation model for monthly-scale regional climate forecast over East China. The systematic errors are formulated for the region on the basis of 10-yr (1991-2000) results of the nested-model system, and of the datasets of the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) and the temperature analysis of the National Meteorological Center (NMC), U.S.A., which are then used for correcting the original forecast by the system for the period 2001-2005. After the assessment of the original and corrected forecasts for monthly precipitation and surface air temperature, it is found that the corrected forecast is apparently better than the original, suggesting that the approach can be applied for improving monthly-scale regional climate dynamical forecast.展开更多
Based on the observations from 239 meteorological stations located in Central China (Henan, Hubei and Hunan provinces), this paper focuses on the climate change facts during 1961- 2010. There was a significant incre...Based on the observations from 239 meteorological stations located in Central China (Henan, Hubei and Hunan provinces), this paper focuses on the climate change facts during 1961- 2010. There was a significant increasing trend in annual mean temperature for Central China during 1961 -2010. The increasing rate was 0.15℃ per decade, which was lower than the national trend. Since the mid-1980s, temperature increasing was obvious. Large increasing rate was observed in the mid-eastern part of Central China. For the four seasons, the increasing rate in winter was the largest (0.27℃ per decade). The increasing rate in the annual mean minimum temperature was larger than that in the annual mean maximum temperature from 1961 to 2010. As a result, the diurnal range of temperature decreased at the rate of -0.10℃ per decade. The extreme high temperature events were increasing while the extreme low temperature events were significantly decreasing. There was no obvious trend in annual precipitation for Central China during 1961-2010. Precipitation in summer and winter significantly increased; change of precipitation in spring was not obvious; precipitation in autumn was decreasing. The decreasing rate of annual rainy days was -3.4 d per decade. The precipitation intensity increased at the rate of 0.25 mm d-1 per decade. Heavy-rain days significantly increased. Spring and summer started earlier while autumn and winter started later. As a result, spring and summer duration was expanding whereas autumn and winter duration shortened.展开更多
This paper deals with a new integrated method of reconstruction and forecasting of climatic changes in future. The method is based on proxy data pollen-spore analysis method, 14C analysis method, nowadays meteorologic...This paper deals with a new integrated method of reconstruction and forecasting of climatic changes in future. The method is based on proxy data pollen-spore analysis method, 14C analysis method, nowadays meteorological data, and data about of solar activity expressed in numbers of W (Wolf). Here we present the results of investigation of sediments of the 2nd Fomich River terrace, Taymyr Peninsula, Russia. The formation of the peat bog started 10500 ± 140 years BP and continued during the entire Holocene. The pollen analysis of the sediment samples of the 2nd Fomich River terrace and the analysis of surface samples from a larch forest, typical of this region, reveals two phytochrones: both climatically preconditioned--tundra phytochrone (I1-4) and forest phytochrone (Ⅱ1-4). The techniques of reconstruction and forecasting of basic elements of climate are presented and discussed in details.展开更多
N'zerekore is a geographical region of Guinea, which houses a weather observatory located at longitude 8.8°, latitude 7.7° and altitude 475 m. This region is of major socio-economic interest for the Country...N'zerekore is a geographical region of Guinea, which houses a weather observatory located at longitude 8.8°, latitude 7.7° and altitude 475 m. This region is of major socio-economic interest for the Country. The climatological study of this region shows the variability of each parameter. The objective of this study was to analyze meteorological parameters trends and to assess the space-time evolution of some agro-climatic risks related to the main trends observed in the meteorological parameters regime of this region. In this study, programming tools were used for processing and analyzing meteorological parameters data, including temperatures, rains, wind, evaporation and storms measured in this observatory from 1931 to 2014. The interannual, annual and daily variations of these parameters were obtained, as well as temperature, precipitation anomalies and agroclimatic indexes trends. The analyzing of these variations explained that September is the rainiest months, and the year 1932, 1957 and 1970 are normal, rainy and dry year, respectively. The evaporation increased since 1971 from January to March and November to December. A positive temperature anomaly was observed since 1973 with the maximum 26-33 ℃ and the minimum 16-21 ℃. A dominant westerly wind with a speed of 2.6 m/s was determined. Agro-climatic parameters in N'zerekore have high variability. From 1931 to 2014, three major periods can be distinguished: a wet period from 1931 to 1977, a dry period from 1978 to 1994 and rainfall variability from 1995 to 2014. The trend of these parameters explains the impact of climate change in this part of the world. This is exacerbated by human activity (deforestation), thus mitigation measures are necessary. It would be useful to extend this study throughout the country.展开更多
Long-term meteorological observation series are fundamental for reflecting climate changes.However,almost all meteorological stations inevitably undergo relocation or changes in observation instruments,rules,and metho...Long-term meteorological observation series are fundamental for reflecting climate changes.However,almost all meteorological stations inevitably undergo relocation or changes in observation instruments,rules,and methods,which can result in systematic biases in the observation series for corresponding periods.Homogenization is a technique for adjusting these biases in order to assess the true trends in the time series.In recent years,homogenization has shifted its focus from the adjustments to climate mean status to the adjustments to information about climate extremes or extreme weather.Using case analyses of ideal and actual climate series,here we demonstrate the basic idea of homogenization,introduce new understanding obtained from recent studies of homogenization of climate series in China,and raise issues for further studies in this field,especially with regards to climate extremes,uncertainty of the statistical adjustments,and biased physical relationships among different climate variables due to adjustments in single variable series.展开更多
An international workshop on urban meteorology. observation and modeling, was jointly held by the Institute of Urban Meteorology ( China ) and the National Center for Atmospheric Research (US) in Beijing, October,...An international workshop on urban meteorology. observation and modeling, was jointly held by the Institute of Urban Meteorology ( China ) and the National Center for Atmospheric Research (US) in Beijing, October, 2004. The workshop was intended to share recent progress in urban meteorological research, discuss issues related to research and development priorities faced by diverse Chinese institutions, and explore collaboration opportunities between Chinese and US research institutions. This article summarizes the major issues discussed at the workshop, including observation on urban boundary layer, urban landuse modeling, socio-economic impacts of weather and climates, and air quality in urban environment. It includes recommendations for future urban meteorology observational and modeling research, and potential collaborative opportunities between China and US.展开更多
Hydrological monitoring and seasonal forecasting is an active research field because of its potential applications in hydrological risk assessment, preparedness and mitigation. In recent decades, developments in groun...Hydrological monitoring and seasonal forecasting is an active research field because of its potential applications in hydrological risk assessment, preparedness and mitigation. In recent decades, developments in ground and satellite measurements have made the hydrometeorological information readily available, and advances in information technology have facilitated the data analysis in a real-time manner. New progress in climate research and modeling has enabled the prediction of seasonal climate with reasonable accuracy and increased resolution. These emerging techniques and advances have enabled more timely acquisition of accurate hydrological fluxes and status, and earlier warning of extreme hydrological events such as droughts and floods. This paper gives current state-of-the-art understanding of the uncertainties in hydrological monitoring and forecasting, reviews the efforts and progress in operational hydrological monitoring system assisted by observations from various sources and experimental seasonal hydrological forecasting, and briefly introduces the current monitoring and forecasting practices in China. The grand challenges and perspectives for the near future are also discussed, including acquiring and extracting reliable information for monitoring and forecasting, predicting realistic hydrological fluxes and states in the river basin being significantly altered by human activity, and filling the gap between numerical models and the end user. We highlight the importance of understanding the needs of the operational water management and the priority to transfer research knowledge to decision-makers.展开更多
基金supported by the National Program on Key Basic Research Project (No. 2010CB951602, 2009CB421401)National Science and Technology Ministry (No. 2008BAK50B07)+1 种基金China Special Fund for Meteorological Research in the Public Interest (No. 200906041-052)the Project of National Natural Science Foundation of China (No. 40805060)
文摘The observation data from ground surface meteorological stations is an important basis on which climate change research is carried out, while the homogenization of the data is necessary for improving the quality and homogeneity of the time series. This paper reviews recent advances in the techniques of identifying and adjusting inhomogeneity in climate series. We briefly introduce the results of applying two commonly accepted and well-developed methods (RHtest and MASH) to surface climate observations such as temperature and wind speed in China. We then summarize current progress and problems in this field, and propose ideas for future studies in China. Along with collecting more detailed metadata, more research on homogenization technology should be done in the future. On the basis of comparing and evaluating advantages and disadvantages of different homogenization methods, the homogenized climate data series of the last hundred years should be rebuilt.
基金the National Basic Research Program of China(973 Program)(No. 2010CB428401)the Special Fund of Climate Change of the China Meteorological Administration (CCSF-09-16)by the National Natural Science Foundation of China(40910177)
文摘Monthly temperature and precipitation time-series for the Zhujiang River Basin are analyzed in order to identify changes in climate extremes. Daily temperature and precipitation data from 1961 to 2007 of 192 meteorological stations are used. Two temperature indicators (monthly mean and monthly maximum mean) and three precipitation indicators (monthly total, monthly maximum consecutive 5-day precipitation, and monthly dry days) are analyzed. Tendencies in all five indicators can be observed. Many stations show significant positive trends (above the 90% confidence level) for monthly mean temperatures and monthly maximum mean temperatures. For all months, a significant increase in temperature from 1961 to 2007 can be observed in the entire basin with the coastal area in particular. Positive trends of precipitation extremes can be observed from January to March. Negative trends are detected from September to November. The number of dry days in October increased significantly at 40% of all meteorological stations. Stations with changes of monthly precipitation extremes are scattered over the Zhujiang River Basin. An aggregation of heat waves and droughts can be detected which is accompanied by significant increases of temperature extremes and the negative tendencies in precipitation extremes. The detection of tendencies in climate station density. extremes essentially relies on a good data quality and high
文摘The task of climate observation data processing is central to the quality of an assessment of future climate change impact. The current state-of-the-art is based on the long-running observation records of the meteorological stations. However, it is common for the developing states to have only relatively short and/or intermittent record histories. The issue becomes even more aggravated under an effort to assess the climatic trends for specific territories with few meteorological stations. The paper offers a simple and effective technique to handle the climate observations; the technique makes the most complete use of an available data set by counting the data provided by all meteorological stations including those with short records and omissions. The method is based on numeric differentiation of source data samples.
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.KZCX2-YW-Q11-03)the National Natural Science Foundation of China(Grant Nos.40975049 and 40810059003)
文摘Enhanced observational meteorological elements,energy fluxes,and the concentration of dust aerosols collected from the Semi-Arid Climate Observatory and Laboratory(SACOL) during a typical dust storm period in March 2010 at Lanzhou were used in this paper to investigate the impact of dust aerosols on near surface atmospheric variables and energy budgets.The results show that the entire dust storm event was associated with high wind velocities and decreasing air pressure,and the air changed from cold and wet to warm and dry and then recovered to its initial state.The response of energy fluxes occurred behind meteorological elements.At high dust concentration periods,the net radiation was significantly less in the daytime and higher at night,while the heat fluxes displayed the same trend,indicating the weakening of the land-atmosphere energy exchange.The results can be used to provide verification for numerical model results in semi-arid areas.
基金National Natural Science Foundation of China (40875067, 40675040)Knowledge Innovation Program of the Chinese Academy of Sciences (IAP09306)National Basic Research Program of China. (2006CB400505)
文摘A nested-model system is constructed by embedding the regional climate model RegCM3 into a general circulation model for monthly-scale regional climate forecast over East China. The systematic errors are formulated for the region on the basis of 10-yr (1991-2000) results of the nested-model system, and of the datasets of the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) and the temperature analysis of the National Meteorological Center (NMC), U.S.A., which are then used for correcting the original forecast by the system for the period 2001-2005. After the assessment of the original and corrected forecasts for monthly precipitation and surface air temperature, it is found that the corrected forecast is apparently better than the original, suggesting that the approach can be applied for improving monthly-scale regional climate dynamical forecast.
基金supported by the Climate Change Special Project of China Meteorological Administration:The Assessment Report Preparation of the Climate Change of Central China (No. CCSF-10-04)
文摘Based on the observations from 239 meteorological stations located in Central China (Henan, Hubei and Hunan provinces), this paper focuses on the climate change facts during 1961- 2010. There was a significant increasing trend in annual mean temperature for Central China during 1961 -2010. The increasing rate was 0.15℃ per decade, which was lower than the national trend. Since the mid-1980s, temperature increasing was obvious. Large increasing rate was observed in the mid-eastern part of Central China. For the four seasons, the increasing rate in winter was the largest (0.27℃ per decade). The increasing rate in the annual mean minimum temperature was larger than that in the annual mean maximum temperature from 1961 to 2010. As a result, the diurnal range of temperature decreased at the rate of -0.10℃ per decade. The extreme high temperature events were increasing while the extreme low temperature events were significantly decreasing. There was no obvious trend in annual precipitation for Central China during 1961-2010. Precipitation in summer and winter significantly increased; change of precipitation in spring was not obvious; precipitation in autumn was decreasing. The decreasing rate of annual rainy days was -3.4 d per decade. The precipitation intensity increased at the rate of 0.25 mm d-1 per decade. Heavy-rain days significantly increased. Spring and summer started earlier while autumn and winter started later. As a result, spring and summer duration was expanding whereas autumn and winter duration shortened.
文摘This paper deals with a new integrated method of reconstruction and forecasting of climatic changes in future. The method is based on proxy data pollen-spore analysis method, 14C analysis method, nowadays meteorological data, and data about of solar activity expressed in numbers of W (Wolf). Here we present the results of investigation of sediments of the 2nd Fomich River terrace, Taymyr Peninsula, Russia. The formation of the peat bog started 10500 ± 140 years BP and continued during the entire Holocene. The pollen analysis of the sediment samples of the 2nd Fomich River terrace and the analysis of surface samples from a larch forest, typical of this region, reveals two phytochrones: both climatically preconditioned--tundra phytochrone (I1-4) and forest phytochrone (Ⅱ1-4). The techniques of reconstruction and forecasting of basic elements of climate are presented and discussed in details.
文摘N'zerekore is a geographical region of Guinea, which houses a weather observatory located at longitude 8.8°, latitude 7.7° and altitude 475 m. This region is of major socio-economic interest for the Country. The climatological study of this region shows the variability of each parameter. The objective of this study was to analyze meteorological parameters trends and to assess the space-time evolution of some agro-climatic risks related to the main trends observed in the meteorological parameters regime of this region. In this study, programming tools were used for processing and analyzing meteorological parameters data, including temperatures, rains, wind, evaporation and storms measured in this observatory from 1931 to 2014. The interannual, annual and daily variations of these parameters were obtained, as well as temperature, precipitation anomalies and agroclimatic indexes trends. The analyzing of these variations explained that September is the rainiest months, and the year 1932, 1957 and 1970 are normal, rainy and dry year, respectively. The evaporation increased since 1971 from January to March and November to December. A positive temperature anomaly was observed since 1973 with the maximum 26-33 ℃ and the minimum 16-21 ℃. A dominant westerly wind with a speed of 2.6 m/s was determined. Agro-climatic parameters in N'zerekore have high variability. From 1931 to 2014, three major periods can be distinguished: a wet period from 1931 to 1977, a dry period from 1978 to 1994 and rainfall variability from 1995 to 2014. The trend of these parameters explains the impact of climate change in this part of the world. This is exacerbated by human activity (deforestation), thus mitigation measures are necessary. It would be useful to extend this study throughout the country.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA05090105)the R&D Special Fund for Public Welfare Industry(Meteorology)(Grant No.GYHY201206013)the National Key Technology R&D program(Grant No.2012BAC22B04)
文摘Long-term meteorological observation series are fundamental for reflecting climate changes.However,almost all meteorological stations inevitably undergo relocation or changes in observation instruments,rules,and methods,which can result in systematic biases in the observation series for corresponding periods.Homogenization is a technique for adjusting these biases in order to assess the true trends in the time series.In recent years,homogenization has shifted its focus from the adjustments to climate mean status to the adjustments to information about climate extremes or extreme weather.Using case analyses of ideal and actual climate series,here we demonstrate the basic idea of homogenization,introduce new understanding obtained from recent studies of homogenization of climate series in China,and raise issues for further studies in this field,especially with regards to climate extremes,uncertainty of the statistical adjustments,and biased physical relationships among different climate variables due to adjustments in single variable series.
文摘An international workshop on urban meteorology. observation and modeling, was jointly held by the Institute of Urban Meteorology ( China ) and the National Center for Atmospheric Research (US) in Beijing, October, 2004. The workshop was intended to share recent progress in urban meteorological research, discuss issues related to research and development priorities faced by diverse Chinese institutions, and explore collaboration opportunities between Chinese and US research institutions. This article summarizes the major issues discussed at the workshop, including observation on urban boundary layer, urban landuse modeling, socio-economic impacts of weather and climates, and air quality in urban environment. It includes recommendations for future urban meteorology observational and modeling research, and potential collaborative opportunities between China and US.
基金National Natural Science Foundation of China,No.41425002National Basic Research Program of China,No.2012CB955403+2 种基金National Youth Top-notch Talent Support Program in ChinaChina Special Fund for Meteorological Research in the Public Interest(Major projects),No.GYHY201506001-7The Beijing Science and Technology Plan Project,No.Z141100003614052
文摘Hydrological monitoring and seasonal forecasting is an active research field because of its potential applications in hydrological risk assessment, preparedness and mitigation. In recent decades, developments in ground and satellite measurements have made the hydrometeorological information readily available, and advances in information technology have facilitated the data analysis in a real-time manner. New progress in climate research and modeling has enabled the prediction of seasonal climate with reasonable accuracy and increased resolution. These emerging techniques and advances have enabled more timely acquisition of accurate hydrological fluxes and status, and earlier warning of extreme hydrological events such as droughts and floods. This paper gives current state-of-the-art understanding of the uncertainties in hydrological monitoring and forecasting, reviews the efforts and progress in operational hydrological monitoring system assisted by observations from various sources and experimental seasonal hydrological forecasting, and briefly introduces the current monitoring and forecasting practices in China. The grand challenges and perspectives for the near future are also discussed, including acquiring and extracting reliable information for monitoring and forecasting, predicting realistic hydrological fluxes and states in the river basin being significantly altered by human activity, and filling the gap between numerical models and the end user. We highlight the importance of understanding the needs of the operational water management and the priority to transfer research knowledge to decision-makers.