EVALUATION OF CHANGES IN HYDROMETEOROLOGICAL CONDITIONS OF RAIN STORM SOIL EROSION IN STEPPE AND FOREST-STEPPE ZONES OF UKRAINE IN CONNECTION WITH CLIMATE CHANGE

Abstract

Problem Statement and Purpose. Modem and forthcoming climate changes inevi­tably change the hydrometeorological conditions of water erosion of soils, the most widespread soil degradation process in Ukraine, the negative consequences of which affect virtually all the components of landscapes and cause huge economic and en­vironmental damage. The most widespread kind of soil erosion in the Steppe and Forest Steppe in Ukraine is the storm water erosion, whose role is increasing due to the wanning of the climate. Accordingly, the purpose of the article is to quantify the change in the hydrometeorological conditions of the stomi washout of the soil within the Steppe and Forest-Steppe of Ukraine in the medium temi (2031-2050). The ob­ject of the study is the hydrometeorological conditions of stomi soil erosion, the subject is the changes in these conditions due to climate change within the Steppe and Forest-Steppe of Ukraine. Data & Methods. In the basis for assessing the change in the hydrometeorological conditions of the soil erosion within the Steppe and Forest-Steppe of Ukraine is laid the forecasted values (“projections”) of average monthly and annual precipita­tion, air temperatures and relative air humidify for 2031-2050 for four regions of Ukraine - West, Center, East and South, published in Sixth National Communication of Ukraine on Climate Change. An assessment of the change in the hydrometeorological conditions of rain storm soil erosion is performed on the basis of the so-called «hydrometeorological factor of storm washout of soil”, the average annual value of which is a parameter of the physico-statistical model of erosion-accumulation of soil, developed at the Odessa 1.1. Mechnikov National University. The hydrometeorological factor of rain storm soil erosion takes into account not only the characteristics of rains, but also the antecedent moistening of the soil. The information basis of the work is the average annual values of the hydrometeorological factor of rain storm washout calculated earlier using data of observations at 22 meteorological stations located in the steppe and forest-steppe zones of Ukraine with a full set of necessary data for the period from 1949 to 1989, monthly air temperatures and the precipitation amounts for four to five «reference» weather stations for each of the four regions within which the Steppe and Forest steppe of Ukraine lies, with observational data from 1949 to 2010, and also the materials of the Climate Kadastr of Ukraine. Results. In comparison with the period 1949-1989, within the Steppe and Forest- steppe of Ukraine in 2031-2050, in general, an increase in the mean annual value of the hydrometeorological factor of storm washout and, correspondingly, the intensity of storm erosion of soils, although significantly different for individual regions, is expected. The region West is the most unfavorable in this respect, in which the growth rate of the hydrometeorological factor of storm washout of soil as compared with 1949- 1989. is estimated at 68%. The least unfavorable is the South region, where a certain increase in the erosion hazard associated with an increase in the amount of precipitation is almost completely offset by the effect of increasing and climate. For the regions the Center and the East an increase in the hydrometeorological factor of the storm washout of soil will be 17% and 13%, respectively.