UN ECOSISTEMA ÓPTIMO

2.2.1.1 Flooding

Worldwide floods have become one of the costliest weather-related hazards, causing large scale human, economic and environmental damages during the recent past. Currently, according to the Association of British Insurers (ABI), worldwide floods are the second costliest, weather-related catastrophe after windstorms (ABI, 2005). Similarly, floods in Europe too seem to have become more destructive, and projections show that this tendency may become even more pronounced (Kundzewicz, 2005). The number of major floods in Europe has also risen from one per year between 1900 and 1974 to 15 a year between 1993 and 2001 (Dlugolecki, 2008). In the context of the UK the situation does not seem to be much different. In England alone, 5.2 million properties, amounting to one in six, are currently at risk of flooding (Environment Agency, 2009a). Flood risk in the UK is expected to further increase in the future (Evans et al., 2004), especially due to the impacts of climate change (Pitt, 2008). Evans et al (2004) identified that in addition to

16 climate change, urbanisation, environmental regulations, rural land management, increasing national wealth, and social impacts as the main drivers for increased future flood risk in the UK. Providing an estimate of how costly floods can be, the total economic cost of the 2007 summer floods; which affected several parts of the UK, was estimated at about £3.2 billion (Chatterton et al., 2010), when about 48,000 homes and 7,300 businesses were flooded (Pitt, 2008).

According to the UK Environment Agency (2009b), about 5.2million properties in England, amounting to one in six, remains at risk of flooding. Further, the national climate change risk assessment for the UK (HM Government, 2012) projects the risk of flooding to increase significantly in the future. Flood risk management is thus identified as an area that requires serious action within the next five years and beyond (HM Government, 2012). As it is neither technically feasible nor economically affordable to make the entire nation completely flood-proof (Environment Agency, 2009a), the Environment Agency recognises that, even with increased investment in flood risk management, about 0.5million properties will still be left at high risk of flooding by 2035, even under the most favourable of the future scenarios considered (Environment Agency, 2009b). This has resulted in a shift in the approach to flood risk management in recent years in the UK. Greater emphasis is now placed on non-structural flood risk management measures where at-risk communities are urged to adapt to flooding (Dawson et al., 2011; Pender and Faulkner, 2011). The Pitt Review recommended the take-up of property flood protection by businesses to enhance their business continuity against flooding (Pitt, 2008) and tasked local authorities to discharge these responsibilities under the Civil Contingencies Act 2004. This is of particular importance to SMEs, as they are increasingly

17 urged to address flooding and other EWEs in their business planning, rather than relying on community-level structural protection measures.

2.2.1.2 Temperature extremes

Global average temperatures have increased by nearly 0.8 ºC since the late 19th century, and have been rising at about 0.2 ºC per decade over the past 25 years (Jenkins et al., 2007). Central Europe experienced an unusually high summer temperature in 2003 due to a heat wave. It is now predicted that such extremely hot summers will become more common in future (Firth and Colley, 2006; Schar et al, 2004; Chase et al, 2006). According to Hulme et al (2002), even currently the hot summer days with daytime temperatures in central England exceeding 25ºC have become more common, almost twice as many on average during the 1990s compared to the first half of the twentieth century. The Stern review (2007) estimates that there will be more days of extreme heat (relative to today) and fewer very cold days in the future, due to the effects of climate change. However, the UK experienced back to back cold winters recently, with temperatures plummeting below records. For instance, parts of the UK experienced their coldest temperatures for November (since the records have begun) in the year 2010 (BBC News, 2010a).

Temperature extremes may create adverse impacts on human health and may also create adverse effects on businesses. Firth and Colley (2006) report that the hot summer of 2003 caused major business disruptions and over 20,000 unexpected deaths, including over 2000 unexpected deaths in UK, directly attributable to the high temperatures. On the other hand, temperature extremes may give rise to many other environmental consequences such as droughts. Loss of harvest due to temperature fluctuations may create increased food prices as it happened in 2003 (Metroeconomica, 2004).

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2.2.1.3 Extreme precipitation

Precipitation is the total quantity of water received by the earth’s surface at a specific place during a specific time period. It includes rainfall and snowfall. All regions of the UK have experienced an increase in the contribution to winter rainfall from heavy precipitation events in past few decades (Jenkins et al., 2007). Referring to the studies of the Intergovernmental Panel on Climate Change, Ekström et al (2005) suggest that in the future there may be more intense rainfall events over many areas in Europe, the UK being no exception. Changes to the magnitude, character and spatial distribution of extreme rainfall may have serious social and economic implications (Fowler et al., 2005). The year 2012 was recorded as the second wettest year in the UK since records begun over 100 years ago, and the top 4 of the 5 wettest years have all been since the year 2000 (Met Office, 2013), suggesting that years with extreme rainfalls are increasing. Evidence suggests that the UK is receiving more rain in short bursts, with extreme rainfalls happening more frequently (Met Office, 2013). High intensity and long lasting rainfall episodes are recognised as major landslide triggering factors (Zêzere et al., 2008) and are expected to contribute to increased flooding (Kay et al., 2006).

The UK experienced a number of winters with heavy snowfall during the recent years. The heavy snowfalls of 2009, 2010, and 2012 are some examples. Heavy snowfall in January 2009 was estimated to lead to about 2000-3000 additional business failures (McWilliams, 2009), and the event was estimated to cost UK businesses about £1 billion (BBC News, 2009). These figures suggest how costly heavy snowfall can be for businesses.

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2.2.1.4 Heatwaves

Heat or anomalously hot weather that lasts for several days, usually accompanied by high humidity is called a heatwave (Tan, 2008). Analysis of climate data has revealed that summer heatwaves have become more frequent in the UK (Hulme et al., 2002; Firth and Colley, 2006). It is predicted that they will become more frequent in future due to climate change (Department of Health, 2007), thus creating more severe impacts. As significant health impacts such as increased rates of mortality are associated with heatwaves, such impacts can be expected to further increase with the perceived increase of heatwave occurrences.

2.2.1.5 Droughts

Although droughts are not a common weather extreme experienced by the UK, some parts of the world commonly experience them. However, the climate change scenarios developed by UKCIP have identified that the risk of droughts occurring will increase in future, if climate change continues (Firth and Colley, 2006). The Stern review (2007) projects that serious droughts will occur more regularly in the UK, particularly in the South East region, as the water availability will be increasingly constrained due to decline of runoff in summer periods.