Forces for Change: Borough-Wide
Climatic
The Test Valley, as elsewhere, is undergoing climatic change to which CO2 emissions are a contributing factor. Since 1900, the average temperature has risen by 0.5C and summer rainfall has decreased. Greater climatic changes are predicted over the next 100 years, which may include warmer weather all year, wetter winters, drier summers and weather extremes including storms and flooding. The range of effects on the Test Valley may include the following:
Summer water shortages: Low flows (and drying out) in chalk streams and rivers in summer, plus a requirement for increased abstraction from the chalk aquifer to meet demands from surrounding urban areas, exacerbating low flows. This may result in extension of winterbournes and affect wetland habitats, increase the risk of fire on heaths and the restrict water abstraction for agriculture and horticultural use.
Flooding: Hand in hand with seasonal water shortages, climate changes are giving rise to sporadic but severe flooding and could lead to the requirement for local flood defences.
Change in crops: Climatic change may give rise to the opportunity for different crops, and affect the economic viability of current cropping regimes.
Increased wind speeds/storms: This will cause damage to woodlands, parklands and crops.
Tidal changes: Rising sea levels are expected to effect tidal patterns, with a consequent effect on estuarine habitats and farming on low lying land alongside tidal shorelines.