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Drought and Spatiotemporal Variability of Forest Fires Across Mexico 被引量:3
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作者 Pompa-García MARíN Camarero J.JULIO +1 位作者 Rodríguez-Trejo DANTE ARTURO Vega-Nieva DANIEL JOSE 《Chinese Geographical Science》 SCIE CSCD 2018年第1期25-37,共13页
Understanding the spatiotemporal links between drought and forest fire occurrence is crucial for improving decision-making in fire management under current and future climatic conditions. We quantified forest fire act... Understanding the spatiotemporal links between drought and forest fire occurrence is crucial for improving decision-making in fire management under current and future climatic conditions. We quantified forest fire activity in Mexico using georeferenced fire records for the period of 2005–2015 and examined its spatial and temporal relationships with a multiscalar drought index, the Standardized Precipitation-Evapotranspiration Index(SPEI). A total of 47975 fire counts were recorded in the 11-year long study period, with the peak in fire frequency occurring in 2011. We identified four fire clusters, i.e., regions where there is a high density of fire records in Mexico using the Getis-Ord G spatial statistic. Then, we examined fire frequency data in the clustered regions and assessed how fire activity related to the SPEI for the entire study period and also for the year 2011. Associations between the SPEI and fire frequency varied across Mexico and fire-SPEI relationships also varied across the months of major fire occurrence and related SPEI temporal scales. In particular, in the two fire clusters located in northern Mexico(Chihuahua, northern Baja California), drier conditions over the previous 5 months triggered fire occurrence. In contrast, we did not observe a significant relationship between drought severity and fire frequency in the central Mexico cluster, which exhibited the highest fire frequency. We also found moderate fire-drought associations in the cluster situated in the tropical southern Chiapas where agriculture activities are the main causes of forest fire occurrence. These results are useful for improving our understanding of the spatiotemporal patterns of fire occurrence as related to drought severity in megadiverse countries hosting many forest types as Mexico. 展开更多
关键词 cluster DROUGHT forest fires GEOSTATISTICS spatial clusters Standardised precipitation-evapotranspiration Index (SPEI)
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Comparative evaluation of impacts of climate change and droughts on river flow vulnerability in Iran 被引量:2
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作者 Zahra Noorisameleh Shahriar Khaledi +3 位作者 Alireza Shakiba Parviz Zeaiean Firouzabadi William AGough MMonirul Qader Mirza 《Water Science and Engineering》 EI CAS CSCD 2020年第4期265-274,共10页
Rivers in arid and semi-arid regions are threatened by droughts and climate change.This study focused on a comparative evaluation of the impacts of climate change and droughts on the vulnerability of river flows in th... Rivers in arid and semi-arid regions are threatened by droughts and climate change.This study focused on a comparative evaluation of the impacts of climate change and droughts on the vulnerability of river flows in three basins with diverse climates in Iran.The standardized precipitation-evapotranspiration index(SPEI)and precipitation effectiveness variables(PEVs)extracted from the conjunctive precipitation effectiveness index(CPEI)were used to analyze the drought severity.To investigate hydrological droughts in the basins,the normalized difference water index(NDWI)and the streamflow drought index(SDI)were calculated and compared.The effects of droughts were assessed under various representative concentration pathway(RCP)scenarios.Changes in the number of wet days and precipitation depth restricted hydrological droughts,whereas an increasing number of dry days amplified their severity.The projected increases in dry days and precipitation over short durations throughout a year under future climate scenarios would produce changes in drought and flood periods and ultimately impact the frequency and severity of hydrological droughts.Under RCP 4.5,an increase in the frequencies of moderate and severe meteorological/hydrological droughts would further affect the Central Desert Basin.Under RCPs 2.6 and 8.5,the frequencies of severe and extreme droughts would increase,but the drought area would be smaller than that under RCP 4.5,demonstrating less severe drought conditions.Due to the shallow depths of most rivers,SDI was found to be more feasible than NDWI in detecting hydrological droughts.©2020 Hohai University.Production and hosting by Elsevier B.V.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Climate change River flow PRECIPITATION Drought index Standardized precipitation-evapotranspiration index Iran
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