Sheaves et al., 2007:

"There is little doubt that coastal and estuarine habitats and ecosystems in the GBR region will be severely impacted by climate change. They are particularly vulnerable to four aspects of climate change: i) alterations in the magnitude, timing and frequency of rainfall, ii) sea level rise, iii) altered frequency and severity of extreme weather events, and iv) major changes in water temperature. Changes to rainfall patterns are likely to have the most diverse and far reaching effects because it is the mixing of fresh and marine waters that give estuaries their unique characters, and because freshwater delivers nutrients from the land that supports estuarine and coastal productivity.

Altered rainfall is likely to profoundly affect individual species and their distributions, the habitats they rely on, the trophic webs that support them and ecological processes like migration and nursery ground function. Changes in rainfall will manifest its effects through impacts on salinity, nutrient delivery and export, flushing, sediment transport, inundation, habitat availability and the cuing of recruits to enter estuarine nurseries (see Figure). Rainfall will also interact strongly with sea level rise to determine crucial connectivity, wetland health and persistence, and nursery ground availability and value, as well as impacting inundation levels and salinity to affect the very nature of estuaries (e.g. shifts between dry and wet tropics estuarine conditions). Changes to the timing and frequency of extreme weather events is likely to disrupt the normal cycle of variability and resetting (essential in maintaining estuarine productivity, trophic structure and habitat diversity), alter patterns of diversity through time, influence the rate of habitat destruction, and change the extent of opening of estuary mouths."

Figure 19.2: Major likely impacts of climate change on coastal and estuarine habitats in the GBR region