Climate Variability and Extremes

Mitigation through information establishing a clearinghouse for loss data

Currently, there are two databases in the public domain that attempt to document hazard events and losses in Latin America, and those mid- to 10 Million 10-100 Million 100 Million-1 Billion 1 Billion Figure 14.2. (a) Total losses from all natural hazards from 1960 through 2004 (b) total losses from only weather-related hazards from 1960 through 2004. Based on the Spatial Hazard Events and Losses Database for the United States (SHELDUS Version 4.2), and adjusted to 2005 US dollars. Figure 14.2....

Genesis of the Risk Prediction Initiative

The large losses resulting from Hurricane Andrew put many insurance companies out of business or in difficult straits, and a significant fraction of capital available for use by the insurance industry was used to pay claims. The resultant depleted pool of capital available for insurance drove up reinsurance prices and increased the potential returns for companies offering reinsurance.1 A number of new property catastrophe reinsurers were formed in Bermuda to take advantage of this business...

Sea level and coral growth

Sea level is predicted to rise over the next 100 years from the thermal expansion of seawater and the melting of continental ice (Intergovernmental Panel on Climate Change IPCC , 2001,2007). This rise will increase the depth of the water column above a coral reef, and as the depth is related to the level of irradiance by the Beer-Lambert law, the intensity of irradiance will decrease. The stability of sea level for the past few thousand years has led to reefs growing up to a point where they...

Illustrative reinsurance example

Reinsurers tend to work on very focused risk portfolios, because they are dealing with risks that are unacceptable to primary insurers. The example below illustrates how such risks could escalate in the future and become unacceptable, even to reinsurers. Suppose that in 2000 the reinsurer assessed there were three possible event outcomes normality, an extreme event defined as a 1-in-100-year probability , and a catastrophe defined as having a 1,000-year return period . Swiss Re's current...

Irradiance and coral growth rate

Schematic Diagram Coral

The abundance of corals in the tropics compared with the extratropics poleward of latitudes 23 , which is apparent from Figure 9.1, is caused by differences in seasonal temperatures and the levels of annual solar irradiance, or insolation. The photosynthetic rates of zooxanthellae are dependent on both light and temperature Muller-Parker and D'Elia, 1997 . As a result, corals are found in warm, clear, shallow waters that have sufficient irradiance necessary for photosynthesis. Reef corals can...

Introduction

Economic losses attributed to natural disasters have increased from US 75.5 billion in the 1960s to US 659.9 billion in the 1990s United Nations Development Programme UNDP , 2004 , for an annual growth rate of approximately 8 . Private sector data also show rising insured losses over a similar period Munich Re, 2001 Swiss Re, 2005 . Both reinsurers and some climate scientists have argued that these increases demonstrate a link between anthropogenically induced global warming and catastrophe...

Modeling coral growth in Curacao

Curacao is completely surrounded by fringing reefs, which provide protection, food, and income to the island population of approximately 150,000. There are several documented natural and anthropogenic threats to the Curacao reefs. Massive coral bleaching impacted the Curacao coral reef in 1987, 1990, and 1995 hurricanes and disease have caused considerable damage and massive coastal development has led to increased sedimentation and sewage, which are also harmful to the reefs Burke and Maidens,...

Multidimensional nature of extreme events

In addition to this potential source of confusion, extreme events have a variety of different attributes and so cannot be completely described by a single number. The multidimensional nature of extreme events is often overlooked in rankings of the events based on only one of the attributes e.g., the category numbers for hurricanes based solely on maximum surface wind speed . Extreme events have attributes such as rate probability per unit time of occurrence For example, a major hurricane is...

Munich Re estimates of climaterelated losses

Munich Re has been compiling statistics on natural disasters for many years because they illustrate the need for risk management. Their definition of what are ''major natural catastrophes'' follows the criteria laid down by the United Nations the affected region's ability to help itself is distinctly overtaxed, interregional or international assistance is necessary, thousands are killed, hundreds ofthousands are made homeless, and there are substantial economic losses and or considerable...

Climate Extremes And Society

The past few decades have brought extreme weather and climate events to the forefront of societal concerns. Ordinary citizens, industry, and governments are concerned about the apparent increase in the frequency of weather and climate events causing extreme, and in some instances, catastrophic, impacts. Climate Extremes and Society focuses on the recent and potential future consequences of weather and climate extremes for different socioeconomic sectors. The book also examines actions that may...

References

A. 2002 . Mortality, growth and reproduction in Scleractinian corals following bleaching on the Great Barrier Reef. Marine Ecology Progress Series, 237, 133-41. Bak, R. P. M. 1976 . The growth of coral colonies and the importance of crustose coralline algae and burrowing sponges in relation with carbonate accumulation. Netherlands Journal of Sea Research, 10, 285-337. Baker, A. C., Stargert, C. J., McClanahan, T. R., and Glynn, P. W. 2004 . Corals' adaptive...

The origin of extreme events

Understanding the processes that lead to the creation of extreme events and how they might change in the future is a key goal of climate science. To help tackle the problem of the origin of extremes, I propose two guiding principles. * The evolutionary principle. Extreme events do not arise spontaneously instead, they evolve continuously from less extreme events and they stop evolving to become even more extreme events. * The stationary principle. Extremes such as local maxima and minima are...

Impacts of extreme events

While many of the extreme events discussed here have been, and will increasingly be, costly in social, economic, and environmental terms, it needs to be emphasized once again that strong impacts are not necessarily or exclusively related to extreme weather events. Indeed, many of the geomorphologic hazards in the Alps are the result of long-term climatic and geological forcings that at some stage result in a particular threshold exceedance leading to sudden and intense slope instabilities....

Normalized insured losses

The work presented in this chapter was motivated by Katz (2002), who modeled total annual economic damage associated with hurricanes with a compound Poisson process. The process is compound since the total number of damaging hurricanes per year is fitted with a Poisson distribution, while the monetary amount of damage for individual hurricanes is fitted by the lognormal distribution. Damage totals are thus represented as a ''random sum,'' with variations in total damage being decomposed into...

Overview of loss models

Hurricane loss models have traditionally consisted of an input set of historical or synthetic storms that constitute a frequency or occurrence model, and additional meteorological, vulnerability, and actuarial components. In support of these components, databases on historical events and their detailed characteristics are necessary. For average annual loss cost estimation, probability distributions governing the stochastic generation of events are also necessary. For a given, fixed exposure,...

Who needs a loss inventory

The United States is exposed to many different types of natural hazards, and to weather and climate hazards in particular. Media-friendly hurricanes batter the coasts while floods, earthquakes, tornadoes, droughts, and other common and powerful hazards affect not only coastal areas but also the interior areas of the country. The destruction caused by Hurricane Katrina along the Gulf Coast in 2005 is just the current placeholder for the next ''big hazard event.'' Death and destruction can occur...

Weatherbattered states

As can be seen in Figure 14.2a, most losses from natural hazards occur along the US coastlines. In considering only weather-related losses, the pattern remains essentially the same, with the exception of California, where earthquake losses are dominant (Figure 14.2b). Interestingly, earthquakes and other geophysical events do not significantly alter the historic spatial pattern of losses. Instead, they simply add another loss burden to areas that also suffer from weather-related losses, mainly...

Underlying problems and approaches

Part of the problem in defining severe convection is the susceptibility of different parts of society to effects of the same weather event. For example, a large amount of small hail less than 2 cm in diameter may have little impact on urban areas, but could be devastating to agricultural interests at certain times of the year and for certain crops. Similarly, strong winds may have minimal impact in an area of grassland used for cattle ranching, whereas the same winds may be damaging in a...

Loss amplification

The traditional approach in catastrophe loss modeling has been to employ an engineering definition of damage as the basis from which to determine insured losses. In both the two major catastrophe losses of the 1990s - Hurricane Andrew in 1992 and the 1994 Northridge earthquake - it had been recognized that an additional factor termed ''demand surge'' was required to reflect all elements of the increase in losses, beyond the expectations of the predicted costs to repair the damages. In the...

How is storm climate variability linked to hemispheric temperature variations

The link between decadal and centennial variations of mean temperature and storminess has hardly been studied, because of the lack of sufficient data. Specifically, it has been argued that a general warming would be associated with elevated water vapor levels, which in turn would be associated with stronger extratropical storms. Obviously, this argument is to first order symmetric, so a general cooling would be associated with less storminess. The history of climate variability in past...

Acknowledgments

We are grateful for the help provided by Irene Fischer-Bruns, Iris Grabemann, and Beate Gardeike. Alexandersson, H., Schmith, T., Iden, K., and Tuomenvirta, H. 1998 . Long-term trend variations of the storm climate over northwest Europe. Global Atmosphere-Ocean System, 6, 97-120. Alexandersson, H., Schmith, T., Iden, K., and Tuomenvirta, H. 2000 . Trends of storms in northwest Europe derived from an updated pressure data set. Climate Research, 14, 71-3. Aspelien, T. 2006 . The use of long-term...

Heavy precipitation events

The Alps particularly are exposed to both extremes of precipitation - i.e., heavy precipitation (including hail) and drought - according to the circulation patterns that are associated with extremes and their persistence. Many of the strong rainfall events result in flooding and geomorphologic hazards such as landslides, rock falls, and debris flows within regions of complex topography. If these events occur in the vicinity of populated regions, the impacts in human and economic terms can be...

Melding science into the catastrophe risk business

Catastrophe risk models play a major role in the world of insurance for catastrophe risk. Risk models cover a variety ofnatural hazards as well as terrorism. The type and geographic range of commercial risk models are continually expanding. Hazards in countries with large amounts of insurance include earthquakes in Japan and the United States tropical cyclones in the United States, Japan, and Australia and winter storms and floods in Europe, as well as smaller-scale events such as tornadoes and...

Midlatitude North America

Mid Latitude Cyclone Over The Usa

We limit the study area for North America to the latitudinal band between the Tropic of Cancer and 53 N north of this band, population and station density becomes sparse, a fact manifested in CRU2 as well as GHCN V2 data gaps Figure 5.4. Same as Figure 5.1, but for North America (a) North American average temperature anomaly relative to the base period 1950-99 from CRU2 observations and the CGCM historical and future scenarios. (b) H&CSI displayed as percentage of North American grid points...

Climate variations

We argue that the annual distribution of insured hurricane losses depends to some extent on preseason climate factors. This conclusion is reasonable given that statistical relationships between US hurricane activity and climate are well established (Bove et al., 1998 Elsner and Kara, 1999 Elsner et al, 1999 Saunders et al., 2000 Elsner et al., 2000a, b, 2001 Elsner, 2003 Elsner et al., 2004 Saunders and Lea, 2005). More importantly for the present work, Jagger et al. (2001) and Jagger and...

Definition of extreme events

Extreme events are generally easy to recognize but difficult to define. This is due to several reasons. First, there is no unique definition for what is meant by the word extreme several definitions are in common use. Second, the concept of extremeness is relative and so strongly depends on context. Third, the words severe, ''rare,'' ''extreme,'' and high-impact are often used interchangeably. 1.2.1 Severe, rare, extreme, or high-impact In an attempt to alleviate some of the confusion, here are...

European storms

This author reported a striking correlation between winter temperatures and the occurrence and strength of great European storms, using the Central England Temperature CET, as measured by the Hadley Centre as a proxy for temperature, and Lamb's Lamb, 1991 record of great storms Chartered Insurance Institute CII , 1994 . The data in Table 13.8 show that storms are twice as frequent in warm months as in medium months, and 150 more common than Table 13.8. Great European storms and winter...

Data on hazard events and losses

There is a wealth of information on natural hazards in the United States. A variety of agencies and groups collect hazard-related information however, differences in their goals result in a patchwork of data coverage. Useful sources of data currently available for analyzing historic and current hazard event and loss trends are summarized in Table 14.1. The mission agencies collecting hazard-related data have a broad range of mandates that are reflected in the type of data they compile and how...

Condensed summary

A comprehensive national loss inventory of natural hazards is the cornerstone for effective hazard and disaster mitigation. Despite federally demanded mitigation plans (Disaster Mitigation Act of 2000, DMA 2000) that are supposed to accurately represent the risks and losses, there still is no systematic and centralized inventory of all hazards and their associated losses (direct, indirect, insured, uninsured, etc.) - at least not in the public domain. While a variety of agencies and groups...

Increasing losses from weatherrelated hazards

Since 1960, dollar losses from natural hazards have steadily increased (Figure 14.1). Weather-related events constitute most of these losses (more than 75 ), with hurricanes, floods, and severe storms (including hail and tornadoes) as the major causal agents. The year 2004 would have been the most costly year, with almost US 30 billion in losses, had there not been Hurricane Katrina in 2005. The tallies for the storm of the century stand currently at more than US 100 billion in damages with...

New Orleans projected flood losses

The flooding in New Orleans covered an estimated 80 of the city, with 55 of the city's properties being inundated by more than 1.2m of water, with maximum flood depths up to 6 m. During the flood, the water washed out oil tanks, sewerage systems, and two major landfill sites, along with several industrial sites, gas stations, and other locations where hazardous materials were stored. Concerns about the health hazards of the polluted floodwaters were among the principal reasons for the...

Changes in temperature extremes

On a regional basis, a number of studies of extremes have been completed as a part of a series of regional workshops coordinated by the joint World Meteorological Organization WMO Climate Variability and Predictability Climate Change Indices CLIVAR CCI Expert Team on Climate Change Detection, Monitoring and Indices ETCCDMI . Each of these workshops used a set software that calculated extremes defined in Frich et al. 2002 . These workshops included the Caribbean Peterson et al., 2002 , southern...

Hurricane activity rates

Since the first generation of models, one of the basic principles of hurricane catastrophe loss modeling had been that activity rates should be based on the average of history (over the maximum time period for which historical observations could be considered complete). For landfalling storms in the United States, this has generally been taken to be the period since 1900. However, hurricane activity in the Atlantic basin had remained persistently high (in all but El Nino years) since 1995, and...

Statistical diagnosis of extreme events

This section will briefly describe some statistical approaches for interpreting extreme events. A more comprehensive discussion is given in the excellent book by Coles 2001 . 1.3.1 Point process modeling of simple extreme events In order to make the analysis more amenable to mathematical modeling, it is useful to neglect important attributes such as temporal duration, spatial scale, and multivariate dependencies. The IPCC 2001 defined ''simple extreme'' events to be ''individual local weather...

Evidence Of Trends In Daily Climate Extremes Over Southern And West Africa

Changes in precipitation and temperature extremes in Central America and northern South America, 1961-2003. Journal of Geophysical Research, 110, D23107, doi 10.1029 2005JD006119. Akinremi, O. O., McGinn, S. M., and Cutforth, H. W. 1999 . Precipitation trends on the Canadian prairies. Journal of Climate, 12, 2996-3003. Alexander, L., et al. 2006 . Global observed changes in daily climate extremes of temperature and precipitation. Journal of Geophysical Research, 111,...

Climate Variability United States Hail

Convective storms play a vital role in weather and climate. They act to redistribute heat, moisture, and trace gases in the vertical and in the horizontal. In the tropics and in the warm season in the mid-latitudes, they provide a significant part of the precipitation. Therefore, they are beneficial to society, Climate Extremes and Society, ed. H. F. Diaz and R. J. Murnane. Published by Cambridge University Press. Cambridge University Press 2008. particularly in agriculture. When convection is...

Extreme precipitation

Increased temperatures lead to an increase in the water-holding capacity of the atmosphere, such that with each 1 C increase we have an increase of about 7 in the water-holding capacity Trenberth et al., 2003 . Furthermore, observations suggest that as this capacity increases with increased temperatures, relative humidity remains more or less constant, resulting in an increase in water vapor in the atmosphere owing to enhanced drying of the surface. Figure 2.5 shows 10 20 30 40 50 60 70 80 90...

W Qw W W W E E Qe E E

How much more intense will heat waves become, on average, in a future with no curbing of greenhouse gas emissions The answer is in this figure. At each point on the map, the color corresponds to a value in degrees Celsius (see legend on the right of the figure). This value is the projected magnitude of the increase in temperature during the three warmest consecutive nights of the summer, in the climate of the end of the twenty-first century (the last two decades, to be precise),...

Standardizing losses in Sheldus

Yet another reason that a comprehensive standardized database of hazard events and losses at the national scale is needed can be seen in the way historical loss data are reported. SHELDUS reports losses by using a conservative ''yardstick,'' meaning that all losses based on SHELDUS should be considered as minimum estimates. This conservative approach is required because the input data, which are derived from different federal agencies, report losses in diverse metrics. Some entities give loss...

Flooding of New Orleans

In the 2005 RMS US Hurricane model (as available in RiskLink 5.0), extreme storm surges were modeled as extending into New Orleans (for hurricanes of category 3 and above), but it had been assumed that there would not be significant breaching of levees and that deep flooding would be prevented by the pumping capacity in the city. These widely shared assumptions had proved highly unconservative (Independent Levee Investigation Team ILIT , 2006). With respect to the potential for levee breaching,...