Climatological features and trends of extreme precipitation during 1979–2012 in Beijing, China

Abstract. In this study, three kinds of hourly precipitation series with the spatial resolution of 0.1° are used to analyze the climatological features and trends of extreme precipitation during the period of 1979–2012 in Beijing, China. The results show that: (1) the spatial distribution of median annual precipitation, with a range from 500 to 825 mm, is similar to that of local topography, which increases from the northwest to the southeast. Taking the urban area as a centre, the inter-annual precipitation in the Beijing area displays an outward decreasing tendency at the maximum rate of 125 mm per decade (125 mm × 10 a−1); (2) extreme precipitation amount, which accounts for 40–48% of total precipitation amount, has a similar spatial distribution to average annual precipitation; (3) the spatial distribution of extreme precipitation days and threshold estimated as the upper 95 percentile are significantly different from that of extreme precipitation, with maximum values concentrated on the urban area and the eastern mountain area, and minimum values in northwest; (4) extreme precipitation days (Ex_pd95) show an opposite distribution to extreme precipitation threshold (Ex_pv95), indicating that areas with greater precipitation threshold may has less precipitation days, and vice versa; (5) an apparent spatiotemporal decreasing tendency is detected in extreme precipitation amount. The downward tendencies are also found in extreme precipitation threshold. Unlike Ex_pv95, in most of the study area, Ex_pd95 is virtually unchanged; (6) downward trends of extreme precipitation is slightly smaller than that of annual precipitation, and the reducing amplitude of north-eastern areas are much higher than the areas in the southwest.

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Spatiotemporal Variability of Precipitation in Beijing, China during the Wet Seasons

Water ◽

10.3390/w12030716 ◽

2020 ◽

Vol 12 (3) ◽

pp. 716 ◽

Cited By ~ 2

Author(s):

Meifang Ren ◽

Zongxue Xu ◽

Bo Pang ◽

Jiangtao Liu ◽

Longgang Du

Keyword(s):

Urban Area ◽

Global Climate ◽

Spatiotemporal Variability ◽

Annual Precipitation ◽

Circulation Index ◽

Intensity Index ◽

Suburban Areas ◽

The Past ◽

Beijing China ◽

Average Annual Precipitation

To comprehensively evaluate the changes in precipitation patterns in the context of global climate change and urbanization, the spatiotemporal variability of precipitation during the wet seasons of 1981–2017 in Beijing was analyzed in this study using up-to-date daily and hourly precipitation data from observation stations. It was concluded that the average annual precipitation in wet seasons showed a downward trend, while the simple daily intensity index (SDII) showed an upward trend. Precipitation in the central urban area of Beijing showed obvious changes from 1981 to 2017; the average annual precipitation in the central urban area was almost as great as that in Miyun country after 2010, which was the storm center for the past three decades. The average annual maximum 3-h and 6-h precipitation in the 2010s was higher than the past three decades, especially in urban and suburban areas. In addition, the atmospheric circulation index, urbanization impact, and topography were all found to be important factors that affect the pattern of precipitation in Beijing.

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Performance evaluation of ensemble precipitation forecasts and satellite products for the spring 2019 severe floods in Iran

10.5194/egusphere-egu21-9089 ◽

2021 ◽

Author(s):

Saleh Aminyavari ◽

Bahram Saghafian ◽

Ehsan Sharifi

Keyword(s):

Spatial Distribution ◽

Weather Prediction ◽

Precipitation Amount ◽

Warning System ◽

Extreme Precipitation Events ◽

Spatial Coverage ◽

Precipitation Estimates ◽

Precipitation Threshold ◽

Precipitation Thresholds ◽

Precipitation Events

In this study, the performance of ensemble precipitation forecasts of three numerical weather prediction (NWP) models within the TIGGE database as well as the integrated multi-satellite retrievals for global precipitation measurement (GPM), namely IMERG-RT V05B, for precipitation estimates were evaluated in recent severe floods in Iran over the March&#8211;April 2019 period. The evaluations were conducted in two modes: spatial distribution of precipitation and the dichotomous evaluation in four precipitation thresholds (25, 50, 75, and 100 mm per day). The results showed that the United Kingdom Met Office (UKMO) model, in terms of spatial coverage and satellite estimates as well as the precipitation amount, were closer to the observations. Although, generally, the models captured the spatial distribution of heavy precipitation events, the hot spots were not located in the correct area. The National Centers for Environmental Forecast (NCEP) model performed well at low precipitation thresholds, while at high thresholds, its performance decreased significantly. On the contrary, the accuracy of IMERG improved when the precipitation threshold increased. The UKMO had better forecasts than the other models at the 100 mm/day precipitation threshold, whereas the Medium-Range Weather Forecasts (ECMWF) had acceptable forecasts in all thresholds and was able to forecast precipitation events with a lower false alarm ratio and better detection when compared to other models. Although, the models and IMERG product underestimated or overestimated the amount of precipitation, but they were able to detect most extreme precipitation events. Overall, the results of this study show the IMERG precipitation estimates and NWP ensemble forecasts performed well in the three major flood events in spring 2019 in Iran. Given wide spread damages caused by the floods, the necessity of establishing an efficient flood warning system using the best precipitation products is advised.&#160;

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Changes in Slight and Extreme Precipitation Events From 1963 to 2017 Over Northern Xinjiang, China

Frontiers in Earth Science ◽

10.3389/feart.2021.622889 ◽

2021 ◽

Vol 9 ◽

Author(s):

Minggang Li ◽

Yong Zhao ◽

Yang Li ◽

Xin Zhou ◽

Shaobo Zhang

Keyword(s):

Extreme Precipitation ◽

Precipitation Amount ◽

Annual Precipitation ◽

Annual Number ◽

Total Annual Precipitation ◽

Northern Xinjiang ◽

Extreme Precipitation Events ◽

Annual Precipitation Amount ◽

Mean Temperature ◽

Different Temperatures

Based on daily measured data from 25 stations in Xinjiang Province from 1963 to 2017, we discuss the statistical characteristics, linear trends, and temporal concentration of slight precipitation (SP) and extreme precipitation (EP) events, and consider relationships between SP and EP events and daily mean temperature. The results show that SP events contribute strongly to the total annual number of wet days, and that EP events contribute strongly to the total annual precipitation amount. In consist with the decrease in SP events and the increase in EP events over the 55-year period, the contribution of SP events to total annual number of wet days has decreased significantly while the contribution of EP events to total annual precipitation amount has increased significantly. SP event usually distributes through most months of the year, whereas EP event usually concentrates in summer (JJA). Influenced by the negative trends for SP events frequency and positive trends of EP events frequency during recent decades, the concentration degree for SP and EP events have significantly increased and decreased, respectively. Distinct differences are found between the relationships of SP events and EP events to daily mean temperature. The daily mean temperature recorded at the stations in Northern Xinjiang on days with SP events was between –35°C and +34°C, and for EP events ranged from –21°C to +30°C. Regionally averaged curves for the change in SP and EP event frequency with temperature have bimodal and unimodal distributions, respectively. Trends for daily mean temperatures and for the frequency of SP events at different temperatures agree well over nearly the entire temperature range, while trends for daily mean temperatures and for the frequency of EP events at different temperatures are not always consistent. These results will help to improve our understanding of the characteristics and variability of precipitation in arid regions within the context of climate warming.

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Elevation Dependency of Precipitation over Southern Slope of Central Himalaya

Jalawaayu ◽

10.3126/jalawaayu.v1i1.36446 ◽

2021 ◽

Vol 1 (1) ◽

pp. 1-14

Author(s):

Shankar Sharma ◽

Nitesh Khadka ◽

Bikash Nepal ◽

Shravan Kumar Ghimire ◽

Nirajan Luintel ◽

...

Keyword(s):

Spatial Distribution ◽

Precipitation Amount ◽

Winter Season ◽

Annual Precipitation ◽

Spatial And Temporal Variation ◽

Mean Annual Precipitation ◽

Eastern Region ◽

Monthly Precipitation ◽

Monsoon Precipitation ◽

Post Monsoon

Precipitation plays vital roles in the global water cycle, knowledge of the spatial and temporal variation of the precipitation is essential to understanding extreme environmental phenomena such as floods, landslides, and drought. In this paper, the integrated characteristics of precipitation during 1980–2016 over Nepal along with the seasonal elevation dependency of precipitation were examined for three different regions over the country using Multi-Source Weighted-Ensemble Precipitation (MSWEP) product. The spatial distribution of mean annual precipitation varies significantly with the highest (lowest) precipitation of ~5500 (~100) mm/year in the Arun valley (Manang and Mustang). The precipitation regime of the country is determined by the contribution of the monthly precipitation amount with distinct spatial gradients between the eastern and the western sides during pre-monsoon, post-monsoon, and winter seasons. On the contrary, the spatial distribution of monsoon precipitation tends to more heterogeneous with visible differences between the lowland, midland, and highlands as similar to the annual one. Further, elevation dependency of seasonal precipitation revealed that the winter and post-monsoon precipitation distribution in western and central are very similar, whereas post-monsoon precipitation was found slightly higher than winter season in the eastern region. The highest precipitation areas in eastern and central region are located between 2000-2500 m, which is between 500 and 1000 m in the western region of the country. Overall, the pre-monsoon, summer monsoon and annual precipitation increases gradually with elevation upto 2500 m and then decreases with increasing elevation, whereas winter and post-monsoon precipitation are almost identical to each elevation interval of 500 m.

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Long-term population dynamics of the red deer and European roe deer at the protected and not-protected areas in Mountain Crimea

Ukrainian Journal of Ecology ◽

10.15421/2017_88 ◽

2017 ◽

Vol 7 (4) ◽

pp. 65-72

Author(s):

V. N. Shmagol' ◽

V. L. Yarysh ◽

S. P. Ivanov ◽

V. I. Maltsev

Keyword(s):

Population Dynamics ◽

Protected Areas ◽

Red Deer ◽

Nature Reserve ◽

Roe Deer ◽

Precipitation Amount ◽

Annual Precipitation ◽

Population Number ◽

The Impact

The long-term population dynamics of the red deer (Cervus elaphus L.) and European roe deer (Capreolus capreolus L.) at the mountain and forest zone of Crimea during 1980-2017 is presented. Fluctuations in numbers of both species are cyclical and partly synchronous. Period of oscillations in the population of red deer is about 25 years, the average duration of the oscillation period of number of roe deer is 12.3 years. During the fluctuations in the number the increasing and fall in population number of the red deer had been as 26-47 %, and roe deer – as 22-34 %. Basing on the dada obtained we have assumed that together with large-scale cycles of fluctuations in population number of both red deer and roe deer the short cycles of fluctuations in the number of these species with period from 3.5 to 7.5 years take place. Significant differences of the parameters of cyclical fluctuations in the number of roe deer at some sites of the Mountainous Crimea: breaches of synchronicity, as well as significant differences in the duration of cycles are revealed. The greatest deviations from the average values of parameters of long-term dynamics of the number of roe deer in Crimea are noted for groups of this species at two protected areas. At the Crimean Nature Reserve the cycle time of fluctuations of the numbers of roe deer was 18 years. At the Karadag Nature Reserve since 1976 we can see an exponential growth in number of roe deer that is continued up to the present time. By 2016 the number of roe deer reached 750 individuals at a density of 437 animals per 1 thousand ha. Peculiarity of dynamics of number of roe deer at some sites proves the existence in the mountain forest of Crimea several relatively isolated groups of deer. We assumed that "island" location of the Crimean populations of red deer and European roe deer, their relatively little number and influence of permanent extreme factors of both natural and anthropogenic origination have contributed to a mechanism of survival of these populations. The elements of such a mechanism include the following features of long-term dynamics of the population: the reduction in the period of cyclic population fluctuations, while maintaining their amplitude and the appearance of additional small cycles, providing more flexible response of the population to the impact of both negative and positive environmental factors. From the totality of the weather conditions for the Crimean population of roe deer the recurring periods of increases and downs in the annual precipitation amount may have relevance. There was a trend of increase in the roe deer population during periods of increasing annual precipitation.

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Fluctuations of Annual Precipitation and Water Resources Quality in Ukraine

Chemistry & Chemical Technology ◽

10.23939/chcht10.04si.621 ◽

2016 ◽

Vol 10 (4s) ◽

pp. 621-629

Author(s):

Valentina Pidlisnyuk ◽

◽

John Harrington JR ◽

Yulia Melnyk ◽

Yuliya Vystavna ◽

...

Keyword(s):

Water Resources ◽

Surface Waters ◽

Precipitation Amount ◽

Ion Concentration ◽

Annual Precipitation ◽

Resource Quality ◽

Phosphate Ion ◽

Regional Trends

The article focuses on examining the influence of fluctuations in annual precipitation amount on the quality of surface waters. Water quality was estimated with data on BOD, COD and phosphate–ion concentration within five selected regions of Ukraine. Analysis of the precipitation data (1991 – 2010) showed different regional trends. Using the statistics, determination of the interconnection between precipitation amount and water resources quality were done. The obtained regularities and associated uncertainties can be used for prediction of changes in water resource quality and as a guide for future adaptation to possible climate change.

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