Table 4 Summary of projected hydro-meteorological changes for each scenario and future period

2000–2050

RCP2.6 [GCMs;7;14]

Average annual precipitation is expected to be slightly decreased (−1.2 %) with a parallel increase of temperature by 1.5 °C on average that could lead to a decrease of about 6.4 % in availability.

ΔΤ (°C)

1.4

1.1

2.2

ΔΡ (%)

−2 %

−6 %

5 %

ΔAv (%)

−8 %

−16 %

9 %

RCP4.5 [GCMs;7;16]

Precipitation is projected to slightly decrease (−3.2 %) and combined with the slightly higher (compared to RCP2.6) temperature increase 1.6 °C, could result to an average decrease in availability by 2.8 %.

ΔΤ (°C)

1.5

1.1

2.1

ΔΡ (%)

−4 %

−8 %

3 %

ΔAv (%)

−1 %

−20 %

13 %

RCP8.5 [GCMs;7;15]

Projections show an average decrease of 4.6 % in average annual rainfall and an average temperature increase of 1.9 °C, leading to a water availability decrease by 14.1 %.

ΔΤ (°C)

1.9

1.4

2.6

ΔΡ (%)

−5 %

−9 %

0 %

ΔAv (%)

−13 %

−28 %

−7 %

B1 [GCMs;3;1]

Projected average annual precipitation is expected to be slightly higher (by 0.5 %) than the control period (1970–2000). Average annual temperature (16.3 °C of 1970–2000 period) could increase by an average of 1.5 °C. We could expect an average increase of water availability by 5 %.

ΔΤ (°C)

1.4

1.1

1.9

ΔΡ (%)

1 %

−1 %

2 %

ΔAv (%)

6 %

1 %

7 %

A2 [GCMs;3;1]

Annual precipitation could slightly decrease (by 2.2 %). Average annual temperature could increase by an average of 1.4 °C and average water availability could be slightly reduced (−2 %).

ΔΤ (°C)

1.5

1.1

1.8

ΔΡ (%)

−3 %

−4 %

0 %

ΔAv (%)

−2 %

−4 %

1 %

A1B [RCMs;10;1]

According to the Ensembles results from 10 RCMs, future projections show an average decrease of 12.2 % in average annual rainfall and an average temperature increase of 1.8 °C, leading to a water availability decrease by 11 %.

ΔΤ (°C)

1.2

0.9

2.0

ΔΡ (%)

−7 %

−17 %

0 %

ΔAv (%)

−10 %

−28 %

14 %

2051-2100

RCP2.6 [GCMs;7;14]

Average annual precipitation is expected to be slightly decreased (−2.4 %) with a parallel increase of temperature by 2.0 °C on average that could lead to a decrease of about 19.8 % in availability.

ΔΤ (°C)

1.8

1.4

3.2

ΔΡ (%)

−2 %

−9 %

2 %

ΔAv (%)

−16 %

−53 %

4 %

RCP4.5 [GCMs;7;16]

Annual precipitation could decrease by 9.3 %, annual temperature could increase by an average of 3.0 °C and average water availability could decrease by 18 % compared to past climate.

ΔΤ (°C)

2.9

2.4

4.1

ΔΡ (%)

−9 %

−16 %

−1 %

ΔAv (%)

−17 %

−37 %

0 %

RCP8.5 [GCMs;7;15]

Projections show an average decrease of average annual rainfall by 19.4 % and an average temperature increase of 5.1 °C, leading to a water availability decrease of −29.6 %.

ΔΤ (°C)

4.9

3.7

6.4

ΔΡ (%)

−21 %

−34 %

−5 %

ΔAv (%)

−27 %

−62 %

−14 %

B1 [GCMs;3;1]

Projected average annual precipitation is expected to decrease slightly (4 %, 989 mm). Average annual temperature could increase by an average of 3.1 °C. During this period we could expect on average 10 % less available water resources.

ΔΤ (°C)

3.1

2.6

3.7

ΔΡ (%)

−1 %

−12 %

−1 %

ΔAv (%)

−6 %

−24 %

−5 %

A2 [GCMs;3;1]

Projected average annual precipitation is expected to decrease by 21 % less in comparison to the period 1970–2000. Average annual temperature could increase by an average of 4.5 °C. Average water availability could decrease by 40 %.

ΔΤ (°C)

4.4

3.9

5.3

ΔΡ (%)

−19 %

−28 %

−18 %

ΔAv (%)

−37 %

−47 %

−36 %

A1B [RCMs;10;1]

Projections show an average decrease of average annual rainfall by 25.2 %, and an average temperature increase of 4.6 °C, leading to a water availability decrease of 48 %.

ΔΤ (°C)

3.3

2.4

5.4

ΔΡ (%)

−25 %

−42 %

−14 %

ΔAv (%)

−38 %

−64 %

−17 %