introduction extreme floods, hyperconcentrated and debris flows are common natural hazards in the basins which located in the northern slops of alborz mountain range (iranian north system). flood occurrence in golestan national park in 2001, 2002 and 2005( hosseinzadeh and jahadi toroghi 2012), yearly flash floods in masuleh catchment( rezaei, 2009), large flood in neka basin in 1999(poorahmad ...

Das, T., et al. (2011). "Potential increase in floods in California's Sierra Nevada under future climate projections." Climatic Change 109: 71-94. California's mountainous topography, exposure to occasional heavily moisture-laden storm systems, and varied communities and infrastructures in low lying areas make it highly vulnerable to floods. An important question facing the state-in terms of pr...

A detailed understanding of microbial ecology in different supraglacial habitats is important due to the unprecedented speed of glacier retreat. Differences in bacterial diversity and community structure between glacial snow and glacial soil on the Chongce Ice Cap were assessed using 454 pyrosequencing. Based on rarefaction curves, Chao1, ACE, and Shannon indices, we found that bacterial divers...

Agricultural ecosystems are important contributors to atmospheric greenhouse gasses (GHGs); however, in situ winter emission data in saline-alkali fields are scarce. Gas samples were collected during different periods, from three rice (R1–R3) and three maize (M1–M3) fields with different soil pH levels and salinity conditions. Carbon dioxide (CO2) emissions in the rice and maize fields decrease...

Climate models indicate that the reduction of surface albedo caused by black-carbon contamination of snow contributes to global warming and near-worldwide melting of ice1,2. In this study, we generated and characterized pure and black-carbonladen snow in the laboratory and verified that black-carbon contamination appreciably reduces snow albedo at levels that have been found in natural settings...

Because of the broad range of altitudes spanned by its catchment, the American River is notable for its occasional, very large winter floods. These floods typically are spawned by warm and exceptionally wet storms that deposit heavy rain or wet snows on broad expanses of the river’s watershed, generating rapid runoff and high streamflows. On flood and longer time scales, the American River is n...

A numerical model that includes the effects of mass transfer between mobile and immobile liquid phases, advection, hydrodynamic dispersion, and melt-freeze episodes was developed to simulate ionic solute transport in melting snow. Model calibration using a tracer-infused laboratory snowpack experiment yielded a dispersivity of 0.05 cm and a mobile-immobile phase mass-transfer coefficient of 4 3...

A continuously running hydrological energy balance model was used to analyse the influence of different snow covers on the formation of large floods within glacierized catchments. Model outputs from three different catchments in the Austrian Alps with glacierizations ranging from 30 to 39 % were statistically interpreted to cover a wide range of possible combinations of areal snow cover distrib...

â  the prediction of maximum temperatures as one of the most important climatic parameters due to climate change, global warming and the recent drought will provide definitely more opportunity for planning and the provision of necessary arrangements for the planners. maximum temperatures are much important in management of natural and water resources, agriculture, development of pests and disea...

The initial isotopic compositions of Nd and Sr in basalts from the Central Siberian Plateau and other major continental flood basalts are reported. The continental flood basalts appear to be the product of partial melting of mantle sources that consist of relatively primitive undifferentiated material and are clearly distinct from midocean ridge basalts, which sample mantle reservoirs that have...