Will climate change become dangerous? This question is examined by assessing likely impacts and key vulnerabilities of projected climate change to 2100 for Australia and New Zealand, as a case study for a developed region of the world. It provides a perspective on the international and environmental need for hydrogen energy.

Results from the IPCC Fourth Assessment Report show that frequencies of potential disasters due to major floods, fires, droughts, heat waves and severe tropical storm surges are projected to increase and that sea level rise is likely to accelerate. Vulnerability is likely to be high for water resources, coastal communities and critical infrastructure and in a number of “hotspots”. Many natural systems, and the services they provide, such as the Great Barrier Reef, rainforests and glaciers, are very likely to change markedly because adaptive capacity is limited. Substantial loss of life is not precluded, especially from heat waves in cities. There will be large scale property damage and high insurance losses from natural disasters as a consequence of more frequent extreme events.

The overall conclusion is that developed countries can reduce vulnerability, provided adaptive capacity can successfully be increased and mitigation measures avoid a pathway of high greenhouse gas emission scenarios. Eventually, adaptive capacity will probably be exceeded. Mitigation is then the only strategy likely to prevent dangerous climate change. It includes implementation of a hydrogen economy to reduce our dependence on fossil fuels, especially for transport.