Table 5 Summary of expected outcomes for surface recession from mechanical and chemical action of rainfall for period 2012–2101

Near future (to 2020)

 Fresh cut stone erodes quickly when first exposed, and then comes towards equilibrium

Medium term (to 2050)

 Rate of loss likely to stabilise after initial exposure. Weathering tests by Albion Stone under current climatic conditions give a recession rate for Portland (Jordan’s basebed) limestone of 3–4 mm every century (http://www.albionstone.com/portland-stone/beds/jordans-basebed/. Accessed 25 Sep 2012)

Far future (to 2101)

 Projected increase in the intensity of precipitation likely to be reflected in an increased rate of recession due to the mechanical action of rain, especially where exposed to predominant winds. The projected increase in rain volume is negligible for most of Ireland thus the Karst effect (clean rain dissolution) is unlikely to increase