Estimating return intervals for extreme climate conditions related to winter disasters and livestock mortality in Mongolia

Abstract. Mass livestock mortality events during severe winters, a phenomenon that Mongolians call dzud, cause the country significant socioeconomic problems. Dzud is an example of compound event, meaning multiple climatic and social drivers contribute to risk occurrence. Existing studies argue frequency intensity dzud are rising due combined effects climate change variability, most notably summer drought winter conditions, on top dynamics such as overgrazing. Summer droughts precondition for because scarce grasses malnutrition, making more vulnerable harsh conditions. However, investigating association between typically look at short time frame (i.e., after 1940), few have investigated or recurrence over century-scale record. This study aims fill gaps in technical knowledge about probability by estimating return periods relevant variables: conditions minimum temperature. We divide into three regions (northwest, southwest, east Mongolia) based index soum (county) level. For droughts, our uses proxy tree-ring-reconstructed Palmer severity (PDSI) 1700–2013. severity, observational data temperature 1901 while inferring Mongolia from instrumental Siberia extend early 19th century. Using generalized extreme value distribution with time-varying parameters, we find vary time, variability increasing all regions. Winter however, does not time. The median 100-year period past 300 years estimated ?26.08 ?C ?27.99 northwest, ?25.31 east. co-occurrence increases 21st analysis suggests continued trend would lead increased vulnerability malnutrition. Prospects insurance also discussed.