Climate Change Impacts on Soil Erosion in the Ceyhan Basin Using the RUSLE Model under the SSP5-8.5 Scenario

Worldwide topsoil loss through erosional processes creates substantial annual losses that threaten global food security and essential ecosystem functions. The Shared Socioeconomic Pathway 5 - Fossil-fueled Development (SSP5-8.5) forecasts reduced overall precipitation volumes, enhanced extreme rainfall events, and substantially elevated erosion susceptibility across the Mediterranean Basin. Within the Ceyhan Basin context, existing research lacks kilometer-resolution precipitation datasets spanning the 1995-2014 and 2041-2060 timeframes under SSP5-8.5 conditions for concurrent R factor calibration procedures. Considering these research gaps, this investigation seeks to assess the SSP5-8.5 pathway following AR6 temporal frameworks for mean annual soil loss rates (t ha⁻¹ yr⁻¹) throughout the Ceyhan Basin employing RUSLE methodology. Soil loss quantification utilized the Revised Universal Soil Loss Equation (RUSLE) framework. Computational analyses were performed using Google Earth Engine (GEE) cloud-based infrastructure at 250 m spatial resolution, incorporating CHIRPS datasets for the 1995-2014 baseline timeframe and NEX-GDDP-CMIP6 collections for the 2041-2060 projection period. Soil erodibility parameter (K) derivation employed SoilGrids 2.0, while topographic parameters originated from SRTM datasets. Conservation management parameter (P) was extracted from Copernicus Global Land Cover Layers collections. Reference period (1995-2014) mean soil loss measured 4.424 t ha⁻¹ yr⁻¹, with projections indicating an increase to 5.182 t ha⁻¹ yr⁻¹ during 2041-2060 under SSP5-8.5 conditions. Rainfall erosivity values demonstrated 7.6% enhancement, with peak values ranging from 239,689 MJ·mm·ha⁻¹·h⁻¹·yr⁻¹ to 258,017 MJ·mm·ha⁻¹·h⁻¹·yr⁻¹. Analysis revealed 93.8% of the study region maintaining existing erosion classifications, while 69,402 hectares will experience transitions from very low to low erosion categories. High-resolution climate dataset integration from CMIP6 combined with transition matrix methodologies indicate emerging erosion hotspots throughout southern and central basin areas with intensified erosion processes in environmentally critical zones.