There is now increasing evidence of a changing climate world-wide, as attested by increases in global average air and ocean temperatures resulting in widespread melting of snow and ice, rising global mean sea-level, as well as changes in ocean salinity.

Changing rainfall and wind patterns, with aspects of extreme weather events, (such as droughts, heavy rainfall intensities, heat waves and tropical cyclone intensity) are producing devastating results for many populations.

Due to our past GHG emissions, a certain degree of future change is unavoidable in the coming decades. The Intergovernmental Panel on Climate Change (IPCC) predicts that we can expect throughout this century (with various degrees of confidence[1]):

• Further warming, with greater changes over land and high Northern latitudes
• More frequent extreme hot temperatures, heat waves and heavy precipitation (with implications for lightning strikes)
• More intense typhoons and hurricanes with stronger wind speeds and heavier precipitation due to increased sea-surface temperatures
• Higher precipitations in high latitudes and reduced precipitations in most subtropical land regions
• Rising sea levels.

The UK has recently experienced exceptional flooding and high temperatures. Transport professionals are becoming more aware of the need to build sustainability into design and material specifications. However, the development of design criteria to reflect forecast changes in climatic conditions, particularly for the UK, does set new challenges. The fact that key parts of our infrastructure are supposed to be designed to last up to 100 years clearly takes on a new dimension with climate change.

The key issues of higher temperatures, changing rainfall, and associated events of flooding, and changing wind storms thus demand a comprehensive review of infrastructure design approaches to safety, durability and sustainability. (CIHT CC&ST, 2008)

Losses from extreme weather-related events have been increasing in the last decades, including in the UK (ABI, 2005), with high temperatures in the UK leading to many road surface pavement and bridge expansion failures. The summer heat- wave of 2003 caused £41 million in emergency services and repair costs due to road subsidence alone (Defra, 2004). By the mid 2040s, the high temperatures in Europe of summer 2003 are predicted to be a 1 in 2 year event, (Stott et al., 2006).

High intense rainfall episodes with saturated field run-off have caused flooding of roads in low-lying areas, (loss of road networks in Norfolk and Gloucester shire). The UK summer floods of 2007 led to many road closures and disrupted six motorways with an overall cost of £191M. Closure of the M1 for 40 hours between junction 31 and 34 alone had a cost estimated by the Highways Agency of £2.3 million (UK EA, 2010).

The UK National Flood Risk Assessment estimated that 10% of the UK major road network is in flood plains and close to 7% has a significant to moderate chance of annual flooding (UK EA, 2009).

Other experienced climate-related impacts on roads have included: earthwork instability of embankments with cutting earth slides blocking roads, culverts surcharging leading to surface flooding, damaged road substructures causing pavements to heave under traffic loads, flows exceeding normal river capacities and affecting bridge foundations , (Workington 2009; Transportation Research Board, 2008; LCCP, 2005).

Roads built on clay sub-soils experience higher shrinkage and expansion with consequential collapse. Increased winter precipitation in the form of snow may require higher salting operations which can lead to higher rates of steel, concrete and vehicle corrosion, thus reducing the useful service life of transport components (Wilson et al., 2002).
With regard to property and their insurers they are well aware of climate change impacts.  In the past decades, global insured losses, caused by weather-related disasters, have increased (ABI, 2005; Mills, 2005). In the North Atlantic basin, increased hurricane intensity has been observed this past century (ABI, 2005): in 2004 alone, the US hurricane season had an economic cost of US$60 billion, of which half was covered by insurance (Mills, 2005).

Many experts consider that climate change will raise uncertainty in catastrophe risk assessments, as well as insurance claims². As a result, many insurers may soon start to consider climate change risk management as part of their actuarial practices when assessing material risks. The consequences for insured transport infrastructure are likely to be higher insurance premiums, lowered limits, non-renewals and reductions in risk coverage or increased deductibles (IPCC WG2, 2007; Mills, 2005). In highly exposed locations, projects may need to be self-insured by making financial provisions to cover future losses.