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The study evaluates climate change impact on river runoff in Albania, forecasting decreased precipitation and increased temperatures, leading to reduced water availability. It assesses vulnerability and consequences on energy production, wetlands, water recycling, and flood risks.
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BALWOIS Conference Water Observation and Information System for Decision Support, Ohrid, 25-29 May 2004 Climate change and the expected impact in water resources in Albania Eglantina Demiraj Bruci, Liri Muçaj, Mirela Bicja Hydrometeorological Institute Albania
CC, expected impact • Preparing of climate change scenarios. • Evaluation of impact of climate change on the mean annual and seasonal river runoff
Climate changes • MAGICC/SCENGEN v. 2.4 (CRU/UEA) MAGICC : mid- range IS92a (reference) SRESA1, SRESA2, SRESB1 and SRESB2 (policy scenarios) Climate sensitivity by 2050 and 2100
Climate scenarios GCMs: HadCM2, UKTR, ECHAM4, CSIRO-TR, UIUC-EQ, GFDLLO To develop the climate scenarios, the change fields scaled in SCENGEN by the global-mean temperature change deriving from MAGICC, are used. • temperature and precipitation changes - 2025, 2050 and 2100 - interpolated from 5°* 5° to 0.5 °* 0.5° resolution • composite pattern of future climate change ( GCM experiments are averaged ).
Expected climate changes warm, little-dry area Annual average mean temperature and precipitation changes (SRESA1, SRESB1)
mean annual runoff first model R = a + b*P + c*EPI second model seasonal scenarios Calibration of the coefficients Simulation of the mean seasonal runoff Evaluation of the average differences (in percentage) between the expected runoff for 18 profiles and the respective values from the reference period (1961-1990). Evaluation of impact on the annual and seasonal river runoff
Impact of CC on the annual river runoff • both models forecast decrease in long-term mean annual runoff • decrease in precipitation and increase in temperature lead to runoff decrease.
Impact of CC on the seasonal river runoff average expected changes in mean runoff by 2025, 2050, 2100
Vulnerability to runoff changes • Under reduced surface flow and increased evaporation, the storage of reservoirs will decrease, which will effect the energy production by hydropower stations. • Because of the stream flows reduction, the wetlands (western part of Albania) would experience both increased demands for water and reduced supply of water, which would decrease wetland area. • Reduction of flow in rivers may put increasing pressure on waste treatment processes, leading to increased water recycling and decline in industrial water use. • Increase of the extreme events may mean an underdesigned reservoir or spillway with potential flood risk. • Other consequences of expected CC include not only changes in total water amount and levels, but also erosion of riverbeds, and modification of turbidity and sediment load.