The primary goal of the study is to analyze the spatial-temporal trends and distribution of flood events in the context of climate change in Armenia. For that purpose, some meteorological parameters, physical-geographical factors and the flood events data were studied for the 1994–2019 period. The linear trends demonstrate an increasing tendency of air temperature and precipitation. Those trends expressed increased flood occurrences, especially for the 2000s, whereas Mann–Kendall (MK) trend test reveals no significant change. The number of flood events reaches its maximum in 2011 with its peak in May. Out of 191 flood events, half of the occurrences are recorded in the flat areas and southern aspects of the mountains (22% of the country's territory). There is a certain clustering of flood events in the areas with up to 5° slopes (66% of flood events). The most flood vulnerable areas were analyzed and mapped via Geographical Information System (GIS). The GIS-based mapping shows the location of flood vulnerable areas in the central, northern parts of the country, and the coastal areas of Lake Sevan. Our methodological approach elaborates the localization of flood-prone sites. It can be used for the flood hazard assessment mapping and risk management.

Existing high-resolution reconstructions of hydroclimate variability in the Caucasus are lacking tree-ring data from Armenian Plateau, the most continental part of the region. Our research presents the first dendrochronological investigation in Armenia. Juniper and oak tree-ring width chronologies were constructed, the longest spanning the last 140 years. The positive influence of spring–summer precipitation and the negative influence of temperature suggest drought stress at the investigated sites. Moving correlation analysis indicated a significant change over time in the sensitivity of investigated trees to climatic variability; juniper, previously sensitive to both temperature and precipitation, has shown especially strong precipitation signals in the recent decades since the local climate has turned more arid. Ongoing climate change increases drought stress in juniper, which may have further consequences on semiarid ecosystems. Our results reveal multiannual droughts recorded by tree rings, emerging in most parts of the Black Sea–Caspian Sea region.

The study concerned the analysis of temporal and spatial variability of floods in the Republic of Armenia (RA). While there are number of reports on flood formation of rivers in RA, the literature lacks results on using nonparametric test results to analyze this disastrous phenomenon. For that purpose, the dynamics of changes in extreme maximum instantaneous runoff, as well as air temperature and precipitation database was evaluated and compared between 1960–2012 for 27 hydrometrical observational and 35 meteorological stations in RA. The Mann-Kendall test with consideration of the autocorrelation function was employed as a non-parametric testto identify any present trends. An increasing tendency of air temperature, decreasing tendency of the atmospheric precipitation and extreme maximum instantaneous river runoff were identified in the studied river-basins. As expected, the warming climate contributed to a gradual melting of accumulated snow in the river-basins in winter, resulting in changes in the extreme maximum instantaneous runoff of the rivers in spring, which significantly reduces the risk of the flood occurrence. Thus, it can be claimed that almost all the river basins of Armenia have a tendency to reduce the risk of floods due to global climate change.

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