scholarly journals Spatial—Temporal Assessment of Historical and Future Meteorological Droughts in China

Atmosphere ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 787
Author(s):  
Rucun Han ◽  
Zhanling Li ◽  
Zhanjie Li ◽  
Yuanyuan Han
Keyword(s):  
North China ◽  
Kendall Test ◽  
Natural Phenomenon ◽  
Historical Period ◽  
Future Period ◽  
The North ◽  
Northern Areas ◽  
The Future ◽  
Negative Impacts ◽  
Temporal Assessment

Drought is a natural phenomenon in which the natural amount of water in an area is below the normal level. It has negative impacts on production in numerous industries and people’s lives, especially in the context of climate change. Investigating the spatial–temporal variation of drought is of great importance in water resource allocation and management. For a better understanding of how drought has changed in China from 1961 to 2020 and will change in the future period of this century (2021–2100), a spatial–temporal assessment of drought based on the standardized precipitation evapotranspiration index (SPEI) was carried out. The trends and characteristics (number, duration, and severity) of historical and future droughts in China were evaluated based on 12-month SPEI by employing the Mann–Kendall test, Sen’s slope and run theory. The similarities, differences, and spatial–temporal evolution of droughts in these two periods were analyzed. The results showed that in the historical period the number of droughts decreased gradually from the south of China to the north. Less frequent drought but with longer duration and stronger severity occurred in the northeast and the northern areas. In the future period, most parts of China are projected to suffer more severe droughts with longer duration, especially for Northeast China, North China, Qinghai–Tibetan Plateau, and Southwest China. The likely increasing severity and duration of droughts in most areas of China in the future makes it very necessary to formulate the corresponding drought prevention and relief strategies to reduce the possible losses caused by droughts.

Assessing the spatio-temporal variation and uncertainty patterns of historical and future projected water resources in China

2013 ◽  
Vol 4 (3) ◽  
pp. 302-316
Author(s):  
Qiuan Zhu ◽  
Hong Jiang ◽  
Changhui Peng ◽  
Jinxun Liu ◽  
Xiuqin Fang ◽  
...  
Keyword(s):  
Climate Change ◽  
Temporal Variation ◽  
Spatial And Temporal Variation ◽  
Historical Period ◽  
Precipitation Pattern ◽  
Climate Change Scenarios ◽  
Emission Scenarios ◽  
Future Period ◽  
Dynamic Global Vegetation Model ◽  
The Future

The spatial and temporal variation and uncertainty of precipitation and runoff in China were compared and evaluated between historical and future periods under different climate change scenarios. The precipitation pattern is derived from observed and future projected precipitation data for historical and future periods, respectively. The runoff is derived from simulation results in historical and future periods using a dynamic global vegetation model (DGVM) forced with historical observed and global climate models (GCMs) future projected climate data, respectively. One GCM (CGCM3.1) under two emission scenarios (SRES A2 and SRES B1) was used for the future period simulations. The results indicated high uncertainties and variations in climate change effects on hydrological processes in China: precipitation and runoff showed a significant increasing trend in the future period but a decreasing trend in the historical period at the national level; the temporal variation and uncertainty of projected precipitation and runoff in the future period were predicted to be higher than those in the historical period; the levels of precipitation and runoff in the future period were higher than those in the historical period. The change in trends of precipitation and runoff are highly affected by different climate change scenarios. GCM structure and emission scenarios should be the major sources of uncertainty.

scholarly journals The Impacts of Climate Change on Maximum Daily Discharge in the Payab Jamash Watershed, Iran

2019 ◽  
Vol 11 (1) ◽  
pp. 1035-1045
Author(s):  
Farzad Parandin ◽  
Asadollah Khoorani ◽  
Ommolbanin Bazrafshan
Keyword(s):  
Climate Change ◽  
21St Century ◽  
Climate Models ◽  
River Flow ◽  
Flow Simulation ◽  
Global Climate Models ◽  
Historical Period ◽  
Future Period ◽  
The Future ◽  
Daily Discharge

Abstract One of the most crucial consequences of climate change involves the alteration of the hydrologic cycle and river flow regime of watersheds. This study was an endeavor to investigate the contributions of climate change to maximum daily discharge (MDD). To this end, the MDD simulation was carried out through implementing the IHACRES precipitation-runoff model in the Payyab Jamash watershed for the 21st century (2016-2100). Subsequently, the observed precipitation and temperature data of the weather stations (1980-2011) as well as 4 multi-model outputs of Global Climate Models (GCMs) under the maximum and minimum Representative Concentration Pathways (RCPs) (2016-2100) were utilized. In order to downscale the output of GCMs, Bias Correction (BC) statistical method was applied. The projections for the 21st century indicated a reduction in Maximum Daily Precipitation (MDP) in comparison with the historic period in the study area. The average projected MDP for the future period was 9 mm/day and 5 mm/ day under 2.6 and 8.5 RCPs (4.6% and 2.6% decrease compared with the historical period), respectively. Moreover, the temperature increased in Jamash Watershed based on 2.6 and 8.5 RCPs by 1∘C and 2∘C(3.7% and 7.4% increase compared with the historical period), respectively. The findings of flow simulation for the future period indicated a decrease in MDD due to the diminished MDP in the study area. The amount of this decrease under RCP8.5 was not remarkable (0.75 m3/s), whereas its value for RCP2.6 was calculated as 40m3/s (respectively, 0.11% and 5.88% decrease compared with the historical period).

scholarly journals Future projections of daily hazy and clear weather conditions over the North China Plain using a Perturbed Parameter Ensemble

2021 ◽  
Author(s):  
Shipra Jain ◽  
Ruth M. Doherty ◽  
David Sexton ◽  
Steven Turnock ◽  
Chaofan Li ◽  
...  
Keyword(s):  
North China Plain ◽  
North China ◽  
Internal Variability ◽  
Weather Conditions ◽  
Future Projections ◽  
The North ◽  
The North China Plain ◽  
The Future ◽  
Physical Parameterizations ◽  
Clear Weather

Abstract. We examine past and future changes in both winter haze and clear weather conditions over the North China Plain (NCP) using a Perturbed Parameter Ensemble (PPE) and elucidate the influence of model physical parameterizations on these future projections for the first time. We use a meteorology-based Haze Weather Index (HWI), which was developed to examine the haze conducive weather conditions for Beijing. We find that the HWI can be used as an indicator of winter haze across the entire NCP due to the extended spatial coherence of the local meteorological conditions. The PPE generated using the UK Met Office HadGEM-GC3 model shows that under a high-emission (RCP8.5) scenario, the frequency of haze conducive weather is likely to increase whereas the frequency of clear weather is likely to decrease in future. However, a change of opposite sign with lower magnitude in the frequencies, though less likely, is also possible. In future, the total number of hazy days for a given winter can be as much as ~3.5 times higher than the number of clear days over the NCP. We also examined the changes in the interannual variability of the frequency of hazy and clear days and find no marked changes in the variability for future periods. The future frequencies of winter hazy and clear days in the PPE are largely driven by changes in zonal-mean mid-tropospheric winds and the vertical temperature gradient over the NCP. We do not find any discernible influence of model physical parameterizations on the future projections of trends in the frequency of hazy or clear days. We find a clear impact of anthropogenic climate change on future trends for both hazy and clear days, however, it is only discernible for specific periods due to the large underlying internal variability in the frequencies of hazy and clear days.

scholarly journals Spatial characteristics analysis of drought disasters in North China during the Ming and Qing Dynasties

2016 ◽  
Author(s):  
Shuoben Bi ◽  
Shengjie Bi ◽  
Changchun Chen ◽  
Athanase Nkunzimana ◽  
Yanping Li ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
North China ◽  
Historical Period ◽  
North West ◽  
Orthogonal Function ◽  
North East ◽  
The North ◽  
Ming And Qing Dynasties ◽  
Characteristics Analysis ◽  
Drought Disaster

Abstract. This paper studies grade sequence of drought disasters in 21 sites in Ming and Qing Dynasties (1470–1912) in North China. Two aspects are explored, in order to study the spatial distribution and characteristics of drought disaster in North China. The reconstruction of the sequence of drought disaster in North China during the Ming and Qing Dynasties was based on Empirical Orthogonal Function (EOF) and on Rotated Empiric Orthogonal Function (REOF). The drought disaster has been divided into several space models and into several sensitive space areas. It can provide an important basis for the better understanding of the spatial distribution of drought disasters in North China during the historical period. The research's results show that: the frequency is high in northern area and is low in southern area of North China. The frequency of drought intensity is high in South-East, low in West China. Meanwhile, the North China can be divided into six main sensitive regions: Middle-east of North China, west of North China, South of North China, East of North China, North-east and North-west of North China.

scholarly journals The Impacts of Water Cycle Components on Streamflow in a Changing Climate of Korea: Historical and Future Trends

2020 ◽  
Vol 12 (10) ◽  
pp. 4260
Author(s):  
Mona Ghafouri-Azar ◽  
Deg-Hyo Bae
Keyword(s):  
Soil Moisture ◽  
River Basin ◽  
Water Cycle ◽  
Hydrologic Model ◽  
Historical Period ◽  
Future Trends ◽  
Water Balance Components ◽  
Future Period ◽  
Global Circulation Models ◽  
The Future

This paper investigates the historical and future trends in water balance components and their impacts on streamflow. The trend analyses were applied to the daily climatic and hydrologic variables from 109 subbasins in Korea during the historical period and future period obtained by a multimodel ensemble of 13 global circulation models (GCMs) of the Coupled Model Intercomparison Project, Phase 5 (CMIP5). A calibrated hydrologic model, the precipitation-streamflow modeling system (PRMS) model, was applied to obtain hydrologic data. The results revealed apparent trends in streamflow, with increases in spring and decreases in the other seasons during the historical period. The reduction (or increase) in the amount of streamflow was counterbalanced by the reduction (or increase) in precipitation, groundwater, and soil moisture, which was mainly impacted by the increase (or reduction) in actual evapotranspiration. However, opposite trends are projected for the future period for streamflow and water cycle components, in which spring and winter are projected to have increasing trends mostly counterbalanced by the decreasing trends in precipitation and groundwater. The reasons for the reduction in streamflow include elevated evapotranspiration compared to precipitation, reduced soil moisture, and a significant decrease in groundwater recharge. In addition, the results of the seasonal variability among basins revealed higher variability in summer for the historical period and in winter for the future period, with maximum variability in the Sumjin River basin, indicating that streamflow fluctuated more strongly in the Sumjin River basin during the historical and future periods.

On Riccia marginata and related species (Ricciaceae, Marchantiophyta)

2012 ◽  
Vol 46 ◽  
pp. 298-305 ◽  
Author(s):  
A. D. Potemkin ◽  
T. Ahti
Keyword(s):  
Related Species ◽  
Lake Ladoga ◽  
Leningrad Region ◽  
Sem Images ◽  
North Shore ◽  
The North ◽  
Molecular Studies ◽  
The Future ◽  
The Town

Riccia marginata Lindb. was described by S. O. Lindberg (1877) from the outskirts of the town of Sortavala near the north shore of Lake Ladoga, Republic of Karelia, Russia. The species has been forgotten in most recent liverwort accounts of Europe, including Russia. Lectotypification of R. marginata is provided. R. marginata shares most characters with R. beyrichiana Hampe ex Lehm. It differs from “typical” plants of R. beyrichiana in having smaller spores, with ± distinctly finely areolate to roughly papillose proximal surfaces and a narrower and shorter thallus, as well as in scarcity or absence of marginal hairs. It may represent continental populations of the suboceanic-submediterranean R. beyrichiana, known in Russia from the Leningrad Region and Karelia only. The variability of spore surfaces in R. beyrichiana is discussed and illustrated by SEM images. A comparison with the spores of R. bifurca Hoffm. is provided. The question how distinct R. marginata is from R. beyrichiana needs to be clarified by molecular studies in the future, when adequate material is available. R. marginata is for the time being, provisionally, included in R. beyrichiana.

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