Study on the Characteristics of Changes in Air Temperature and Precipitation in Shenyang in Recent 50 Years

Based on the data of monthly average air temperature,extreme maximum,minimum air temperature and precipitation of Shenyang from 1960 to 2009,the climate changes and its characteristics in Shenyang in recent 50 years were comprehensively analyzed and studied.The results showed that the increasing trend of air temperature in recent 50 years was obvious.With the rising of the air temperature,the precipitation in Shenyang City showed a decreasing trend.

Effects of temperature and precipitation on drought trends in Xinjiang, China

The characteristics of drought in Xinjiang Uygur Autonomous Region(Xinjiang),China have changed due to changes in the spatiotemporal patterns of temperature and precipitation,however,the effects of temperature and precipitation—the two most important factors influencing drought—have not yet been thoroughly explored in this region.In this study,we first calculated the standard precipitation evapotranspiration index(SPEI)in Xinjiang from 1980 to 2020 based on the monthly precipitation and monthly average temperature.Then the spatiotemporal characteristics of temperature,precipitation,and drought in Xinjiang from 1980 to 2020 were analyzed using the Theil-Sen median trend analysis method and Mann-Kendall test.A series of SPEI-based scenario-setting experiments by combining the observed and detrended climatic factors were utilized to quantify the effects of individual climatic factor(i.e.,temperature and precipitation).The results revealed that both temperature and precipitation had experienced increasing trends at most meteorological stations in Xinjiang from 1980 to 2020,especially the spring temperature and winter precipitation.Due to the influence of temperature,trends of intensifying drought have been observed at spring,summer,autumn,and annual scales.In addition,the drought trends in southern Xinjiang were more notable than those in northern Xinjiang.From 1980 to 2020,temperature trends exacerbated drought trends,but precipitation trends alleviated drought trends in Xinjiang.Most meteorological stations in Xinjiang exhibited temperature-dominated drought trend except in winter;in winter,most stations exhibited precipitation-dominated wetting trend.The findings of this study highlight the importance of the impact of temperature on drought in Xinjiang and deepen the understanding of the factors influencing drought.

Observed changes in surface air temperature and precipitation in the Hindu Kush Himalayan region over the last 100-plus years

In this paper, we analyzed the long-term changes in temperature and precipitation in the Hindu Kush Himalayan (HKH) region based on climate datasets LSAT-V1.1 and CGP1.0 recently developed by the China Meteorological Administration. The analysis results show that during 1901e2014 the annual mean surface air temperature over the whole HKH has undergone a significant increasing trend. We determined the change rates in the mean temperature, mean maximum temperature, and mean minimum temperature to be 0.104
C per decade, 0.077
C per decade, and 0.176
C per decade, respectively. Most parts of the HKH have experienced a warming trend, with the largest increase occurring on the Tibetan Plateau (TP) and south of Pakistan. The trend of precipitation for the whole HKH is characterized by a slight decrease during 1901e2014. During 1961e2013, however, the trend of the annual precipitation shows a statistically significant increase, with a rate of 5.28% per decade and has a more rapid increase since the mid-1980s. Most parts of northern India and the northern TP have experienced a strong increase in the number of precipitation days (daily rainfall 1 mm), whereas Southwest China and Myanmar have experienced a declining trend in precipitation days. Compared to the trends in precipitation days, the spatial pattern of trends in the precipitation intensity seems to be more closely related to the terrain, and the higher altitude areas have shown more significant upward trends in precipitation intensity during 1961e2013.

Climate Trends of Temperature, Precipitation and River Discharge in the Abbay River Basin in Ethiopia

Projecting future changes of streamflow in the Abby River Basin (ARB) is important for planning and proper management of the basin system. The current study conducted in five stations of the Abbay river basin, and investigated the annual temperature, precipitation, and river discharge variability using the Innovative trend analysis method, Mann-Kendall, and Sen’s slope test estimator. The result showed a slightly increasing trend of annual precipitation in Assoa (Z = 0.71), Bahir Dar (Z = 0.13), and Gonder (Z = 0.26) stations, while a significant increasing trend was observed in Nedgo (Z = 2.45) and Motta (Z = 1.06) stations. Interestingly, the trend of annual temperature in Assosa (Z = 5.88), Bahir Dar (Z = 3.87), Gonder (Z = 4.38), Nedgo (Z = 4.77), and Motta (Z = 2.85) was abruptly increased. The average mean temperature has increased by 0.2°C in the past 36 years (1980 to 2016). The extreme high temperature was observed in the semi-dry zone of northern Ethiopia. During the study period, a significant declining trend of the river discharge was recorded, and the river discharge was sharply decreased from 1992 onwards. The results of the current study showed annual variability of river discharge, precipitation, and temperature of the study area of the basin that could be used as a basis for future studies.

Future Changes in Temperature and Precipitation Extremes in the State of Rio de Janeiro (Brazil)

In this study, we document the air temperature and precipitation changes between present-day conditions and those projected for the period 2041-2070 in the state of Rio de Janeiro (Brazil) by means of Eta driven by HadCM3 climate model output, considering the variation among its four ensemble members. The main purpose is to support studies of vulnerability and adaptation policy to climate change. In relation to future projections of temperature extremes, the model indicates an increase in average minimum (maximum) temperature of between +1.1°C and +1.4°C (+1.0°C and +1.5°C) in the state by 2070, and it could reach maximum values of between +2.0°C and +3.5°C (+2.5°C and +4.5°C). The model projections also indicate that cold nights and days will be much less frequent in Rio de Janeiro by 2070, while there will be significant increases in warm nights and days. With respect to annual total rainfall, the Northern Region of Rio de Janeiro displays the greatest variation among members, indicating changes ranging from a decrease of -350 mm to an increase of +300 mm during the 21st century. The southern portion of the state has the largest increase in annual total rainfall occurring due to heavy rains, ranging from +50 to +300 mm in the period 2041-2070. Consecutive dry days will increase, which indicates poorly time distributed rainfall, with increased rainfall concentrated over shorter time periods.

Detection of Changes on Temperature and Precipitation Features in Istanbul(Turkey)

In this study, the changes in the data of Istanbul’s precipitation and temperature and the features of these changes were analyzed by different methods. In the analyses the daily precipitation and temperature data sets of Florya and Goztepe Meteorological Stations which have similar locational features were used. These sets were recorded between 1960 and 2013 (for 54 years). In order to emphasize the differentiations in the last 15 years the analyses were conducted comparatively both for the 15-year and for the 54-year periods and then the results were evaluated. The changes in the monthly, annual and seasonal quantity, type and frequency of the precipitation in the form of rain and the features of the temperature’s monthly, annual and seasonal changes, the De Martonne aridity index and the Thornthwaite climate classification were carried out. The results showed that during the years from 1999 to 2013 the climate type of Istanbul changed from semi-humid climate to arid and less-humid climate. Most notably the precipitation during the warm periods has decreased, but the frequency of the intense rain has increased and the majority of these episodes of intense rain coincided with the warm periods. Other determinations were the rise in the annual average temperature and the extension of the warm periods in a year. This differentiation of the temperature features can lead to the aggravation of the evaporation and it can be effective for a longer period during the year. Being aware of this differentiation in the features of precipitation and temperature and taking these data into consideration in all sorts of planning and managing strategies have a special importance for the 14 million or more people living in Istanbul.

Long-term variability of air temperature and precipitation conditions in the Polish Carpathians

Mountain regions are sensitive to climate changes, which make them good indicators of climate change. The aim of this study is to investigate the spatial and temporal variability of air temperature and precipitation in the Polish Carpathians. This study consists of climatological analyses for the historical period 1851-2010 and future projections for 2021-2100. The results confirm that there has been significant warming of the area and that this warming has been particularly pronounced over the last few decades and will continue in the oncoming years.Climate change is most evident in the foothills;however, these are the highest summits which have experienced the most intensive increases in temperature during the recent period. Precipitation does not demonstrate any substantial trend and has high year-to-year variability. The distribution of the annual temperature contour lines modelled for selected periods provides evidence of the upward shift of vertical climate zones in the Polish Carpathians,which reach approximately 350 meters, on average,what indicates further ecological consequences as ecosystems expand or become extinct and when there are changes in the hydrological cycle.

Trends in Indices of Extreme Temperature and Precipitation in Iran over the Period 1960-2014

Climate extremes can have many negative effects on different sectors. Globally, observations show significant changes in the characteristics of extreme events. We examined trends in extreme temperature and precipitation indices in Iran during the period 1960-2014. We present results from 33 quality controlled and homogenous synoptic stations (excluding stations with excessive missing data). For each station, we calculate 27 indices characterizing extreme temperature and precipitation. For all indices (including Rx5DAY, CWD, R95p, R99p, GSL and TXn) positive, negative, and insignificant trends were obtained. Generally, there were negative trends in R10mm, R20mm, R25mm, CDD, PRCPTOT, FD, TN10p, TX10p, CSDI and positive trends in Rx1DAY, SDII, SU25, TR20, TXx, TNn, TNx, TN90p, TX90p and WSDI at most stations. There is a decreasing trend in the magnitude and frequency of cold extremes and an increasing trend in magnitude and frequency of warm extremes over the observational record, which is consistent with previous research reporting the warming trends of the climate.

Analysis on Variations of the Temperature and Precipitation in North Slope Area of the Western Tianshan in Recent 50 Years

[Objective] The research aimed to analyze variation characteristics of the temperature and precipitation in north slope area of the Western Tianshan in recent 50 years.[Method] According to temperature and rainfall data from 1961 to 2010 at three meteorological stations in north slope area of the Western Tianshan,climate change in the zone in recent 50 years was analyzed by using linear trend analysis method and 5-year sliding average method.[Result] The temperature in north slope area of the Western Tianshan showed significant warming trend.The annual average temperature significantly increased at 0.3 ℃/10 a in recent 50 years.But rise rates of the temperature in different seasons were different:autumn> winter> spring> summer.The annual rainfall in north slope area of the Western Tianshan in recent 50 years overall presented relative increase trend.Seen from annual rainfall,it significantly increased at 16.9 mm/10 a.Seen from seasonal rainfall,except in autumn,rainfalls in other three seasons in the past 50 years all showed significant increase trends,with amplitude of 3.2-11.2 mm/10 a.The largest increase amplitude was in summer.After a small precipitation peak in the 1980s,autumn rainfall slightly declined in the past 20 years.[Conclusion] The climate in north slope area of the Western Tianshan become warm and wet.

Review on the Impact of Climate Change on Great Lakes Region’s Agriculture and Water Resources

This study investigates the multifaceted impacts of climate change on the Midwest region of the United States, particularly the rising temperatures and precipitation brought about by hot weather activities and technological advances since the 19th century. From 1900 to 2010, temperatures in the Midwest rose by an average of 1.5 degrees Fahrenheit, which would also lead to an increase in greenhouse gas emissions. Precipitation is also expected to increase due to increased storm activity and changes in regional weather patterns. This paper explores the impact of these changes on urban and agricultural areas. In urban areas such as the city of Chicago, runoff from the increasing impervious surface areas poses challenges to the drainage system, and agriculture areas are challenged by soil erosion, nutrient loss, and fewer planting days due to excessive rainfall. Sustainable solutions such as no-till agriculture and the creation of grassland zones are discussed. Using historical data, recent climate studies and projections, the paper Outlines ways to enhance the Midwest’s ecology and resilience to climate change.

Prediction of Climate Change in the 21^(st) Century in Dalian Area under the Various Emission Scenarios

By using the simulative results of more than 20 climate system models which were provided by the fourth assessment report of the Intergovernmental Panel on Climate Change(IPCC),the climate change in Dalian area in the 21st century under the different scenarios(SRES A2,SRES A1B and SRES B1) were analyzed and predicted with the multi-model's aggregative simulative results via the interpolation downscaling calculation.The results showed that the climate in Dalian would have the obvious warming and wetting tendency in the 21st century as a whole.The annual average warming tendency of air temperature would be 2.45-3.46 ℃/100 years,and the annual precipitation increase trend would be 5.8%-16.3% per 100 years.The warming in winter would be the most obvious,and the precipitation increase would be comparatively obvious in winter and spring.The precipitation decrease would be comparatively obvious in autumn in the previous period of 21st century.In A2,A1B and B1 scenarios,the air temperatures in the late period of 21st century would respectively be 3.46,3.44 and 2.45 ℃ higher than in the ordinary years,and the annual precipitation would respectively be 16.3%,11.8% and 5.79% more than in the ordinary years.

Effect of climate change on seasonal monsoon in Asia and its impact on the variability of monsoon rainfall in Southeast Asia

Global warming and climate change is one of the most extensively researched and discussed topical issues affecting the environment.Although there are enough historical evidence to support the theory that climate change is a natural phenomenon,many research scientists are widely in agreement that the increase in temperature in the 20 th century is anthropologically related.The associated effects are the variability of rainfall and cyclonic patterns that are being observed globally.In Southeast Asia the link between global warming and the seasonal atmospheric flow during the monsoon seasons shows varying degree of fuzziness.This study investigates the impact of climate change on the seasonality of monsoon Asia and its effect on the variability of monsoon rainfall in Southeast Asia.The comparison of decadal variation of precipitation and temperature anomalies before the 1970 s found general increases which were mostly varying.But beyond the 1970 s,global precipitation anomalous showed increases that almost corresponded with increases in global temperature anomalies for the same period.There are frequent changes and a shift westward of the Indian summer monsoon.Although precipitation is observed to be 70%below normal levels,in some areas the topography affects the intensity of rainfall.These shifting phenomenon of other monsoon season in the region are impacting on the variability of rainfall and the onset of monsoons in Southeast Asia and is predicted to delay for 15 days the onset of the monsoon in the future.The variability of monsoon rainfall in the SEA region is observed to be decadal and the frequency and intensity of intermittent flooding of some areas during the monsoon season have serious consequences on the human,financial,infrastructure and food security of the region.

Analysis on the Climate Change Characteristics in Recent 50 Years in Qixinghe Wetland of Heilongjiang Province

Based on the daily temperature and precipitation data during 1961-2007 in 81 meteorological stations of Heilongjiang Province,the climate change trend characteristics of temperature and precipitation in Heilongjiang Province,Shuangyashan area,Baoqing County and Qixinghe Wetland were contrasted and analyzed by adopting the climatology statistics method. The results showed that the temperature change trend in Qixinghe Wetland was consistent with the temperature warming trends in Heilongjiang Province and Shuangyashan area. The annual average lowest temperature was the most obvious in the temperature warming trend,and the annual average temperature was the second. The annual average highest temperature was the third. Qixinghe Wetland had the important regulation effect on the local(Baoqing) climate. The annual precipitation in recent 50 years in Baoqing County,Qixinghe Wetland presented the decline trend and in Heilongjiang Province,Shuangyashan area presented the increase trend as a whole. In the trend which the temperature obviously rose,and the precipitation declined overall in Qixinghe Wetland,the protection of Qixinghe Wetland maybe faced with the restriction of water scarcity condition in the water resources aspect. One of important ways which solved with the water scarcity problem in Qixinghe Wetland maybe was strengthening the artificial effect weather work and using sufficiently the cloud water resources.

Impact of Urbanization on Low-Temperature Precipitation in Beijing during 1960–2008

Daily precipitation and temperature records at 13 stations for the period 1960-2008 were analyzed to identify climatic change and possible effects of urbanization on low-temperature precipitation [LTP, precipitation of ≥ 0.1 mm d^-1 occurring under a daily minimum temperature （Tmin） of ≤ 0℃] in the greater Beijing region （B JR）, where a rapid process of urbaniza tion has taken place over the last few decades. The paper provides a climatological overview of LTP in B JR. LTP contributes 61.7% to the total amount of precipitation in B JR in the cold season （November-March）. There is a slight increasing trend [1.22 mm （10 yr）^-1] in the amount of total precipitation for the cold season during 1960-2008. In contrast, the amount of LTP decreases by 0.6 mm （10 yr）^-1. The warming rate of Train in B JR is 0.66℃ （10 yr）^-1. Correspondingly, the frequency of LTP decreases with increasing Tmin by -0.67 times per ℃. The seasonal frequency and amount of LTP in southeast B JR （mostly urban sites） are 17%-20% less than those in the northwestern （rural and montane sites）. The intensity of LTP for the urban sites and northeastern B JR exhibited significant enhancing trends [0.18 and 0.15 mm d^- 1 （10 yr）^- 1, respectively]. The frequency of slight LTP （〈0.2 mm d^-1） significantly decreased throughout B JR [by about -15.74% （10 yr）^-1 in the urban area and northeast B JR], while the contribution of the two heaviest LTP events to total LTP amount significantly increased by 3.2% （10 yr） ^-1.

Recent Progress in Studies of Climate Change in China

An overview of basic research on climate change in recent years in China is presented. In the past 100 years in China, average annual mean surface air temperature （SAT） has increased at a rate ranging from 0.03℃ （10 yr）-1 to 0.12℃ （10 yr）-1. This warming is more evident in northern China and is more significant in winter and spring. In the past 50 years in China, at least 27% of the average annual warming has been caused by urbanization. Overall, no significant trends have been detected in annual and/or summer precipitation in China on a whole for the past 100 years or 50 years. Both increases and decreases in frequencies of major extreme climate events have been observed for the past 50 years. The frequencies of extreme temperature events have generally displayed a consistent pattern of change across the country, while the frequencies of extreme precipitation events have shown only regionally and seasonally significant trends. The frequency of tropical cyclone landfall decreased slightly, but the frequency of sand/dust storms decreased significantly. Proxy records indicate that the annual mean SAT in the past a few decades is the highest in the past 400-500 years in China, but it may not have exceeded the highest level of the Medieval Warm Period （1000 1300 AD）. Proxy records also indicate that droughts and floods in eastern China have been characterized by continuously abnormal rainfall periods, with the frequencies of extreme droughts and floods in the 20th century most likely being near the average levels of the past 2000 years. The attribution studies suggest that increasing greenhouse gas （GHG） concentrations in the atmosphere are likely to be a main factor for the observed surface warming nationwide. The Yangtze River and Huaihe River basins underwent a cooling trend in summer over the past 50 years, which might have been caused by increased aerosol concentrations and cloud cover. However, natural climate variability might have been a main driver for the mean and extreme precipitation variations observed over the past century. Climate models generally perform well in simulating the variations of annual mean SAT in China. They have also been used to project future changes in SAT under varied GHG emission scenarios. Large uncertainties have remained in these model-based projections, however, especially for the projected trends of regional precipitation and extreme climate events.

Effects of climate change on water resources in Tarim River Basin, Northwest China

Based on hydrology, temperature, and precipitation data from the past 50 years, the effects of climate change on water resources in Tarim River Basin in Northwest China were investigated. The long-term trends of the hydrological time series were detected using both parametric and nonparametric techniques. The results showed that the increasing tendency of the temperature has a 5% level of significance, and the temperature increased by nearly 1℃ over the past 50 years. The precipitation showed a significant increase in the 1980s and 1990s, and the average annual precipitation exhibited an increasing trend with a magnitude of 6.8 mm per decade. A step change occurred in both the temperature and precipitation time series around 1986. The streamflow from the headwater of the Tarim River exhibited a significant increase during the last 20 years. The increase in temperature, precipitation, and streamflow may be attributed to global climate change.

Characteristics of Climate Change in Northern Xinjiang in 1961–2017, China

Xinjiang is located in the core China’s‘Belt and Road’development,and northern Xinjiang is an important region for economic development.In recent years,due to the strong influence of global climate change and human disturbance,regional climate instability and ecological-economic-social system sensitivity have grown.In this paper,seasonal,interannual,interdecadal,spatial,abrupt,and periodic variations of temperature and precipitation in northern Xinjiang were analyzed using daily surface air temperature and precipitation data from 49 meteorological stations during 1961–2017.At the same time,the driving factors of climate change are discussed.Methods included linear regression,cumulative anomaly,the Mann-Kendall test,and Morlet wavelet analysis.The results indicated that during the study period,annual mean temperature and annual precipitation increased significantly at rates of 0.35℃/10 yr and 13.25 mm/10 yr,respectively,with abrupt changes occurring in 1994 and 1986.Annual mean temperature and annual precipitation in all four seasons showed increasing trends,with the maximum increases in winter of 0.42℃/10 yr and 3.95 mm/10 yr,respectively.The general climate in northern Xinjiang showed a trend towards increasingly warm and humid.In terms of spatial distribution,the temperature and precipitation in high mountainous areas increased the most,while basins areas increased only slightly.Periodic change analysis showed that annual mean temperature and annual precipitation experienced two climatic shifts from cold to warm and dry to wet,respectively.Population change,economic development and land use change are important factors affecting climate change,and more research should be done in this field.

Analysis of Characteristics of Climate Change from 1951 to 2009 at Jinzhou City

With routine meteorological data from 1951 to 2009 at Jinzhou City,the variation characteristics of the temperature,precipitation,sunlight,wind speed and evaporation were analyzed.The results showed that the annual average temperature increased significantly and sunshine decreased in the last 59 years at Jinzhou city.Annual precipitation and the average speed were significantly decreased.Evaporation augmented and the average evaporation was 3.1 times than the average precipitation.The sunshine time was positively correlated with evaporation and was negatively correlated with annual precipitation.

Analysis on the Characteristics of Climate Changes in the Surrounding Area of Qinghai Lake

[Objective] The aim was to study the characteristics of climate changes in the surrounding area of Qinghai Lake.[Method] Based on the data of temperature,precipitation and sunshine hours from 5 representative meteorological stations in the surrounding area of Qinghai Lake during 1961-2007,the annual,seasonal and decadal variation of meteorological factors were analyzed.[Result] In recent 47 years,temperature showed obvious increase trend in the surrounding area of Qinghai Lake,and annual average temperature increased with the climatic tendency of ≥0.30 ℃/10 a,while annual average minimum temperature increased more significant than annual average temperature and annual average maximum temperature;annual mean precipitation decreased with the climatic tendency of-3.67 mm/10 a,and precipitation in spring and autumn reduced obviously,while precipitation in summer and winter increased slightly;annual sunshine hours also showed decrease trend with the climatic tendency of-1.79 h/10 a,while sunshine hours decreased most obviously in summer,and next came winter,while there was no obvious decrease in spring and autumn.[Conclusion] The study could provide theoretical references for the effective prevention of meteorological disasters in the surrounding area of Qinghai Lake.

Complex network analysis of climate change in the Tarim River Basin, Northwest China

The complex network theory provides an approach for understanding the complexity of climate change from a new perspective.In this study,we used the coarse graining process to convert the data series of daily mean temperature and daily precipitation from 1961 to 2011 into symbol sequences consisting of five characteristic symbols(i.e.,R,r,e,d and D),and created the temperature fluctuation network(TFN)and precipitation fluctuation network(PFN)to discover the complex network characteristics of climate change in the Tarim River Basin of Northwest China.The results show that TFN and PEN both present characteristics of scale-free network and small-world network with short average path length and high clustering coefficient.The nodes with high degree in TFN are RRR,d RR and Re R while the nodes with high degree in PFN are rre,rrr,eee and err,which indicates that climate change modes represented by these nodes have large probability of occurrence.Symbol R and r are mostly included in the important nodes of TFN and PFN,which indicate that the fluctuating variation in temperature and precipitation in the Tarim River Basin mainly are rising over the past 50 years.The nodes RRR,DDD,Re R,RRd,DDd and Ree are the hub nodes in TFN,which undertake 19.71%betweenness centrality of the network.The nodes rre,rrr,eee and err are the hub nodes in PFN,which undertake 13.64%betweenness centrality of the network.