Syndicate content

Climate Normals

A new `Climate Normal' needed

Alan Miller's picture

The impact of climate change on investment and development is fundamental but is yet to be appreciated, or some in cases even understood. One related issue is a seemingly obscure technical calculation, the use of “Climate Normals” – a standard way of estimating the weather expected in a particular location for any given day. Such estimates have enormous significance for planning power plants, ports, water systems, roads, and long-lived infrastructure.

The difference between temperatures in the ‘70s (a cool period) and the ‘00s (the warmest decade on record) can mean large increases in summer peak demand. The planning of water supply and demand will similarly be dramatically affected with change in temperature and precipitation. Getting it wrong can mean serious under or over investment, with social as well as economic disruption.

The concept of Climate Normals was originally mandated by the WMO and IMO in the 1930s, initially calculated and updated every 30 years. In 1956, the same organizations recommended updates more frequently, every decade. In 2011, the leading US center for archiving and summarizing climate data, National Climate Data Center (NCDC), released the new Climate Normals that cover the period between 1981 and 2010, replacing the previous 1971-2000 installment.