This publication focuses on a threat from the Natural Catastrophe and Climate threat class: a ‘freeze’ event. Extended periods of extreme cold weather have caused severe disruptions and significant economic losses to the United Kingdom and other European and North American economies in recent years. International trading networks rely on clear and timely deliveries via road, rail, sea and air. Extreme weather limits and disrupts the flow of international trade, creating choke points that impact the global network.
This document provides an introduction and summary of the causes of the threat and an analysis of the many consequences (human, agricultural, infrastructural, commercial and social) of extended periods of extremely cold weather. A catalogue of historical events is provided, detailing the various solar, volcanic, and climatological phenomena causing the freeze, with some detailed examples illustrating the impact caused in each case. Finally, a magnitude scale is provided allowing for estimation of impact based on the number of ‘freezing’ degree days.