Analysis of Spatiotemporal Variability in Extreme Climate and Potential Driving Factors on the Yunnan Plateau (Southwest China) during 1960–2019

Global warming is increasing the frequency and intensity of extreme weather events around the world. The extreme climate in plateau and mountainous areas is sensitive and fragile. Based on the software Rclimdex 1.0, the spatio-temporal variation characteristics of 27 extreme climate indices at 120 meteorological stations were calculated in Yunnan from 1960 to 2019. The results show that the extreme temperature is rising, and the warming rate at night is higher than that in the daytime. It showed a trend of warming and drying, and precipitation was concentrated into more intense bursts. Extreme temperature cold indices (TX10p, TN10p, FD0, ID0, and CSDI) were negatively correlated with extreme precipitation indices (R × 5day, PRCPTOT, R10 mm, R20 mm, and R25 mm). Extreme temperature warmth indices (TX90p and TN90p) were positively correlated with extreme precipitation indices (R × 5day, CWD, PRCPTOT, R10 mm, R20 mm, and R25 mm). The change rate of extreme temperature does not increase linearly with altitude. The increase in middle-altitude and high-altitude areas is higher than that in low-altitude areas. Compared with ENSO and AO, NAO is a vital circulation pattern affecting the extreme climate in Yunnan. The influence of NAO on Yunnan’s extreme climate indices is most significant in the current month and the second month that follows. NAO was negatively correlated with extreme temperature warm indices (TN90p, TX90p, SU25, and TR20). NAO positively correlates with the extreme cold temperature indices (TN10p and TX10p). Except that ENSO has a significant effect on CDD, the effect of the general circulation patterns on the extreme temperature indices was more significant than that on the extreme precipitation indices in Yunnan. The results of this study are helpful to further understand and predict the characteristics of extreme climatic events and the factors affecting their geographical locations and atmospheric circulation patterns in Yunnan.

Download Full-text

Changes in extreme climate indices in Sarajevo (Bosnia and Herzegovina)

Glasnik srpskog geografskog drustva ◽

10.2298/gsgd2102001g ◽

2021 ◽

Vol 101 (2) ◽

pp. 1-21

Author(s):

Slobodan Gnjato ◽

Tatjana Popov ◽

Marko Ivanisevic ◽

Goran Trbic

Keyword(s):

Bosnia And Herzegovina ◽

Extreme Precipitation ◽

Extreme Temperature ◽

The Arctic ◽

Climate Indices ◽

East Atlantic ◽

Extreme Climate ◽

Extreme Precipitation Indices ◽

Precipitation Indices ◽

Temperature Indices

The study analyzes trends in extreme climate indices in Sarajevo (Bosnia and Herzegovina). Based on daily maximum temperatures, daily minimum temperatures and daily precipitation during the 1961-2016 periods, a set of 27 indices recommended by the CCl/CLIVAR Expert Team for Climate Change Detection and Indices (ETCCDI) was calculated in the RClimDex (1.0) software. Given the results, the extreme temperature indices displayed a warming tendency throughout the year (most prominent in summer). The positive trends in warm temperature indices were stronger than the downward trends in cold ones. The highest trend values were estimated for TXx, TNx, TX90p, TN90p, WSDI, SU25 and SU30. The extreme precipitation indices displayed trends mixed in sign (annually and seasonally), but all statistically insignificant. However, upward trends in R99p, RX1day, RX5day, SDII, R10mm and R20mm suggest an increase in the magnitude and frequency of intense precipitation events. Moreover, significant changes in distribution of majority temperature indices were determined, whereas shifts in precipitation indices were mostly insignificant. The observed changes in extreme temperature indices are related with large-scale atmospheric circulation patterns (primarily the East-Atlantic pattern) and the Atlantic Multidecadal Oscillation. The negative correlation with the North Atlantic Oscillation, the East Atlantic/West Russia pattern and the Arctic Oscillation is found for majority of extreme precipitation indices.

Download Full-text

Vegetation Dynamics and Diverse Responses to Extreme Climate Events in Different Vegetation Types of Inner Mongolia

Atmosphere ◽

10.3390/atmos9100394 ◽

2018 ◽

Vol 9 (10) ◽

pp. 394 ◽

Cited By ~ 3

Author(s):

Li Na ◽

Risu Na ◽

Jiquan Zhang ◽

Siqin Tong ◽

Yin Shan ◽

...

Keyword(s):

Extreme Precipitation ◽

Inner Mongolia ◽

Climate Changes ◽

Extreme Temperature ◽

Vegetation Growth ◽

Extreme Climate ◽

Extreme Precipitation Indices ◽

Precipitation Indices ◽

The Relationship

As the global climate has changed, studies on the relationship between vegetation and climate have become crucial. We analyzed the long-term vegetation dynamics and diverse responses to extreme climate changes in Inner Mongolia, based on long-term Global Inventory Monitoring and Modelling Studies (GIMMS) NDVI3g datasets, as well as the eight extreme precipitation indices and six extreme temperature indices that are highly correlated with the occurrence of droughts or floods, heat or cold temperature disasters, and vegetation growth in Inner Mongolia. These datasets were analyzed using linear regression analysis, the Hurst exponent index, residual analysis, and the Pearson correlation analysis. The results showed the following: (1) The vegetation dynamical changes exhibited trends of improvement during 1982 to 2015, and 68% of the vegetation growth changes in Inner Mongolia can be explained by climate changes. (2) The extreme precipitation indices exhibited a slight change, except for the annual total wet–day precipitation (PRCPTOT). The occurrence of extreme cold temperatures showed a significant decline, while the occurrence of extreme warm temperatures showed an upward trend in Inner Mongolia. (3) The typical steppe, desert steppe, and forest steppe regions are more sensitive to extreme large precipitation, and the forest regions are more sensitive to extreme warm temperatures. (4) Extreme precipitation exhibits a one-month lagged effect on vegetation that is larger than the same-month effects on the grassland system. Extreme temperature exhibits same-month effects on vegetation, which are larger than the one-month lagged effects on the forest system. Therefore, studies of the relationship between extreme climate indices and vegetation are important for performing risk assessments of droughts, floods, and other related natural disasters.

Download Full-text

Spatial Heterogeneity and Complexity of the Impact of Extreme Climate on Vegetation in China

Sustainability ◽

10.3390/su13105748 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5748

Author(s):

Shuang Li ◽

Feili Wei ◽

Zheng Wang ◽

Jiashu Shen ◽

Ze Liang ◽

...

Keyword(s):

Extreme Precipitation ◽

Vegetation Index ◽

Precipitation Amount ◽

Extreme Temperature ◽

Climate Indices ◽

Natural Ecosystems ◽

Extreme Climate ◽

Dry Spell ◽

Compound Type ◽

The Impact

The impact of extreme climate on natural ecosystems and socioeconomic systems is more serious than that of the climate’s mean state. Based on the data of 1698 meteorological stations in China from 2001 to 2018, this study calculated the 27 extreme climate indices of the Expert Team on Climate Change Detection and Indices (ETCCDI). Through correlation analysis and collinearity diagnostics, we selected two representative extreme temperature indices and three extreme precipitation indices. The spatial scale of the impact of extreme climate on Normalized Difference Vegetation Index (NDVI) in China during the growing season from 2001 to 2018 was quantitatively analyzed, and the complexity of the dominant factors in different regions was discussed via clustering analysis. The research results show that extreme climate indices have a scale effect on vegetation. There are spatial heterogeneities in the impacts of different extreme climate indices on vegetation, and these impacts varied between the local, regional and national scales. The relationship between the maximum length of a dry spell (CDD) and NDVI was the most spatially nonstationary, and mostly occurred on the local scale, while the effect of annual total precipitation when the daily precipitation amount was more than the 95th percentile (R95pTOT) showed the greatest spatial stability, and mainly manifested at the national scale. Under the current extreme climate conditions, extreme precipitation promotes vegetation growth, while the influence of extreme temperature is more complicated. As regards intensity and range, the impact of extreme climate on NDVI in China over the past 18 years can be categorized into five types: the humidity-promoting type, the cold-promoting and drought-inhibiting compound type, the drought-inhibiting type, the heat-promoting and drought-inhibiting compound type, and the heat-promoting and humidity-promoting compound type. Drought is the greatest threat to vegetation associated with extreme climate in China.

Download Full-text

Spatiotemporal Trend Analysis of Precipitation Extremes in Ho Chi Minh City, Vietnam During 1980–2017

International Journal of Disaster Risk Science ◽

10.1007/s13753-020-00311-9 ◽

2020 ◽

Author(s):

Nguyen Trong Quan ◽

Dao Nguyen Khoi ◽

Nguyen Xuan Hoan ◽

Nguyen Ky Phung ◽

Thanh Duc Dang

Keyword(s):

Extreme Precipitation ◽

Southern Oscillation ◽

Precipitation Extremes ◽

Spatiotemporal Variability ◽

Ho Chi Minh City ◽

Annual Rainfall ◽

Extreme Precipitation Events ◽

Extreme Precipitation Indices ◽

Precipitation Indices ◽

The City

Abstract In this study, the spatiotemporal variability of trends in extreme precipitation events in Ho Chi Minh City during the period 1980–2017 was analyzed based on several core extreme precipitation indices (Rx1day, Rx5day, CDD, CWD, R20mm, R25mm, R95p, and SDII). The non-parametric Mann–Kendall and Sen’s slope methods were used to compute the statistical strength, stability, and magnitude of trends in annual rainfall, as well as the extreme precipitation indices. We found that 64% of the stations had statistically significant upward trends in yearly rainfall, with high magnitudes frequently observed in the northern and southern regions of the city. For the extreme precipitation indices, only SDII and R25mm showed dominantly significant trends. Additionally, there were increasing trends in the frequency and duration at the southern and central regions of the city during the study period. Furthermore, El Niño-Southern Oscillation and Pacific Decadal Oscillation positively correlated with the duration and negatively correlated with the intensity and frequency of extreme precipitation. Thus, water management plans should be adjusted appropriately to reduce the severe impacts of precipitation extremes on communities and ecosystems.

Download Full-text

Spatiotemporal Changes in Precipitation Extremes over Canada and Their Teleconnections to Large-Scale Climate Patterns

Journal of Hydrometeorology ◽

10.1175/jhm-d-18-0004.1 ◽

2019 ◽

Vol 20 (2) ◽

pp. 275-296 ◽

Cited By ~ 7

Author(s):

Yang Yang ◽

Thian Yew Gan ◽

Xuezhi Tan

Keyword(s):

Extreme Precipitation ◽

Large Scale ◽

Specific Humidity ◽

Climate Indices ◽

Extreme Precipitation Events ◽

Daily Precipitation Data ◽

Climate Patterns ◽

Extreme Precipitation Indices ◽

Precipitation Indices ◽

Precipitation Events

Abstract In the past few decades, there have been more extreme climate events occurring worldwide, including Canada, which has also suffered from many extreme precipitation events. In this paper, trend analysis, probability distribution functions, principal component analysis, and wavelet analysis were used to investigate the spatial and temporal patterns of extreme precipitation events of Canada. Ten extreme precipitation indices were calculated using long-term daily precipitation data (1950–2012) from 164 Canadian gauging stations. Several large-scale climate patterns such as El Niño–Southern Oscillation (ENSO), Pacific decadal oscillation (PDO), Pacific–North American (PNA), and North Atlantic Oscillation (NAO) were selected to analyze the relationships between extreme precipitation and climate indices. Convective available potential energy (CAPE), specific humidity, and surface temperature were employed to investigate potential causes of trends in extreme precipitation. The results reveal statistically significant positive trends for most extreme precipitation indices, which means that extreme precipitation of Canada has generally become more severe since the mid-twentieth century. The majority of indices display more increasing trends along the southern border of Canada while decreasing trends dominated the central Canadian Prairies. In addition, strong teleconnections are found between extreme precipitation and climate indices, but the effects of climate patterns differ from region to region. Furthermore, complex interactions of climate patterns with synoptic atmospheric circulations can also affect precipitation variability, and changes to the summer and winter extreme precipitation could be explained more by the thermodynamic impact and the combined thermodynamic and dynamic effects, respectively. The seasonal CAPE, specific humidity, and temperature are correlated to Canadian extreme precipitation, but the correlations are season dependent, which could be positive or negative.

Download Full-text

Trend analysis of extreme precipitation indices in the southern part of Java

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/653/1/012032 ◽

2021 ◽

Vol 653 (1) ◽

pp. 012032

Author(s):

W P Abdila ◽

B D A Nugroho

Keyword(s):

Trend Analysis ◽

Extreme Precipitation ◽

Extreme Precipitation Indices ◽

Precipitation Indices

Download Full-text

Understanding Precipitation Characteristics of Afghanistan at Provincial Scale

10.21203/rs.3.rs-365073/v1 ◽

2021 ◽

Author(s):

Shakti Suryavanshi ◽

Nitin Joshi ◽

Hardeep Kumar Maurya ◽

Divya Gupta ◽

Keshav Kumar Sharma

Keyword(s):

Extreme Precipitation ◽

Asian Country ◽

Annual Precipitation ◽

Precipitation Pattern ◽

Precipitation Trend ◽

Extreme Precipitation Events ◽

Changing Patterns ◽

Extreme Precipitation Indices ◽

Precipitation Indices ◽

Precipitation Events

Abstract This study examines the pattern and trend of seasonal and annual precipitation along with extreme precipitation events in a data scare, south Asian country, Afghanistan. Seven extreme precipitation indices were considered based upon intensity, duration and frequency of precipitation events. The study revealed that precipitation pattern of Afghanistan is unevenly distributed at seasonal and yearly scales. Southern and Southwestern provinces remain significantly dry whereas, the Northern and Northeastern provinces receive comparatively higher precipitation. Spring and winter seasons bring about 80% of yearly precipitation in Afghanistan. However, a notable declining precipitation trend was observed in these two seasons. An increasing trend in precipitation was observed for the summer and autumn seasons, however; these seasons are the lean periods for precipitation. A declining annual precipitation trend was also revealed in many provinces of Afghanistan. Analysis of extreme precipitation indices reveals a general drier condition in Afghanistan. Large spatial variability was found in precipitation indices. In many provinces of Afghanistan, a significantly declining trends were observed in intensity-based (Rx1-day, RX5-day, SDII and R95p) and frequency-based (R10) precipitation indices. The duration-based precipitation indices (CDD and CWD) also infer a general drier climatic condition in Afghanistan. This study will assist the agriculture and allied sectors to take well-planned adaptive measures in dealing with the changing patterns of precipitation, and additionally, facilitating future studies for Afghanistan.

Download Full-text

Historical Spatial and Temporal Climate Trends in Southern Ontario, Canada

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-16-0290.1 ◽

2017 ◽

Vol 56 (10) ◽

pp. 2767-2787 ◽

Cited By ~ 3

Author(s):

Hussein Wazneh ◽

M. Altaf Arain ◽

Paulin Coulibaly

Keyword(s):

Climate Models ◽

Global Climate ◽

Global Climate Models ◽

Climate Indices ◽

Total Precipitation ◽

Southern Ontario ◽

Temperature And Precipitation ◽

Annual Total ◽

Precipitation Indices ◽

Temperature Indices

AbstractSpatial and temporal trends in historical temperature and precipitation extreme events were evaluated for southern Ontario, Canada. A number of climate indices were computed using observed and regional and global climate datasets for the area of study over the 1951–2013 period. A decrease in the frequency of cold temperature extremes and an increase in the frequency of warm temperature extremes was observed in the region. Overall, the numbers of extremely cold days decreased and hot nights increased. Nighttime warming was greater than daytime warming. The annual total precipitation and the frequency of extreme precipitation also increased. Spatially, for the precipitation indices, no significant trends were observed for annual total precipitation and extremely wet days in the southwest and the central part of Ontario. For temperature indices, cool days and warm night have significant trends in more than 90% of the study area. In general, the spatial variability of precipitation indices is much higher than that of temperature indices. In terms of comparisons between observed and simulated data, results showed large differences for both temperature and precipitation indices. For this region, the regional climate model was able to reproduce historical observed trends in climate indices very well as compared with global climate models. The statistical bias-correction method generally improved the ability of the global climate models to accurately simulate observed trends in climate indices.

Download Full-text

Trend of Extreme Precipitation over Sumatera Island for 1981-2010

Agromet ◽

10.29244/j.agromet.33.1.41-51 ◽

2019 ◽

Vol 33 (1) ◽

pp. 41-51

Author(s):

. Misnawati ◽

Mega Perdanawanti

Keyword(s):

Extreme Precipitation ◽

Ecosystem Health ◽

The Other ◽

Economic Losses ◽

Positive Trend ◽

Climate Extreme ◽

Precipitation Data ◽

Extreme Precipitation Indices ◽

Precipitation Indices ◽

Climate Events

Extreme climate events have significant impacts on various sectors such as agriculture, ecosystem, health and energy. The issue would lead to economic losses as well as social problems. This study aims to investigate the trend of extreme precipitation in Sumatera Island based on observed data during 30-year period, 1981–2010. There are ten indices of climate extreme as defined by ETCCDMI, which were tested in this study, including PRCPTOT, SDII, CDD, CWD, R10, R50, R95p, R99p, Rx1day and Rx5day. Then, the trend was analyzed based on the Mann-Kendall statistic, performed on the time series of precipitation data. The result shows that there was positive trend of extreme precipitation found in most stations over Sumatera, either statistically significant or insignificant. In each extreme precipitation indices, the number of observed stations indicating the insignificant change is higher than the significant one. This research also found that some indices including SDII, Rx1day, R50, R95p and R99p, showed a significantly-positive trend followed by a higher intensity of wetter and heavier events of extreme precipitation over Sumatera. On the other hand, the wet spell (CWD) index shows a negative trend (α=0.05).

Download Full-text