On 29 August 2005 Hurricane Katrina made landfall on the Louisiana coastline. Just shy of one month later, Hurricane Rita tore across southern Florida, hitting the Texas-Louisiana border after crossing the Gulf of Mexico. About one month after that Hurricane Wilma, the most intense tropical storm on record in the Atlantic basin, ripped across the Gulf in the opposite direction, devastating parts of the Caribbean, Mexico and Florida. This 3-storm combination resulted in one of the most widespread loss recovery situations the US property/casualty market had ever seen. Even with the collegiate spirit and robust wordings in the market there were issues, particularly with business interruption. Some companies are still dealing with claims a decade later.

Astonishingly there has been only one major hurricane landfall in the US in the last eight years, despite a number forecasts to the contrary during that period. This year, the US National Hurricane Centre has forecast a "below-average" hurricane season for 2015. This low in North American hurricane activity has been a key factor in the recent softening of market conditions. Indeed, general property market conditions are the softest they have been since before 2000. Unfortunately, with soft markets can come soft drafting.

Industry Loss Warranties – the simple choice?

One type of cover taking centre stage at the 1 January renewals was the Industry Loss Warranty (ILW). ILWs, developed in the 1980s, have been on the increase since Superstorm Sandy in 2012. These covers are designed to respond once a loss has hit a certain threshold on an industry-wide basis. They usually nominate a specific organisation's reported figure to be the benchmark – for example Property Claims Services (PCS), Swiss Re's sigma or Munich Re's NatCAT service.

It is essential to draft these types of wordings tightly, however, as pitfalls abound. The most common relate to the suitability of the nominated index. For example, where an ILW's trigger is phrased as "non-marine property losses arising in North America" in excess of GBP 5 billion following a named windstorm, it would be prudent to nominate a publication that provides its estimates based on non-marine property only (some publications do not differentiate between marine and non-marine property in compiling their indices). If the trigger specifies a geographical region, it is important to ensure the publication nominated also covers that region, and not just a subset.

Where the publication nominated does not suit the trigger a reinsurer may use this to challenge the claim, and may even be permitted to substitute alternative figures proving its case. Where the policy includes an arbitration clause, the situation may become more difficult still, as in many cases arbitration clauses provide that the arbitrators need not rely on the strict letter of the law in coming to their decision. Arbitrators are often keen to find a "middle way" where the legal (and commercial) situation is not clear cut. In addition, if successful, the reinsured will not be able to rely on the outcome of the arbitration in relation to any other disputes arising under the same (or same type of) policy with its other reinsurers. All of a sudden a simple cover has turned into a complicated one.

Hours clauses take their time

Another area to consider when dealing with natural catastrophe claims is the so-called "hours clause". This clause allows the reinsured to aggregate losses arising from the same originating cause within a set time frame. Traditionally this is 24-48 hours for a hurricane or 72 hours for flood, and 168 hours for other non-named perils.

Recently, however, hours clauses have emerged that go rather beyond tradition. Frequently hours clauses now have time periods in relation to flood or snow-related losses of 504 consecutive hours, or 21 days. In addition, some hours clauses now permit the reinsured, as "sole judge", to aggregate losses from other catastrophes into the same loss, so long as those catastrophes occur within the relevant time period. We expect these sorts of clauses, particularly where the reinsured has sole discretion to deal with the losses as it chooses, to be difficult to challenge.

Beware the unexpected threats of climate change

Hurricanes and typhoons are often considered the "paradigm" example when it comes to considering the effects of and losses arising from natural catastrophes. "Superstorm Sandy" started life as a hurricane, although it became "extratropical" on reaching New Jersey. It continued to produce wide-ranging damage, including severe flooding in New York City.

It is worth bearing in mind that not all of the effects of climate change result in hot-weather events. Rising temperatures result in moisture being trapped in the air for longer periods, which results in more intense storms – both rain and snow. Perhaps one of the starkest recent examples of this is the series of snowstorms affecting New England earlier this year, which produced record-breaking snowfalls coupled persistent cold temperatures (making it difficult for municipalities to clear the snow from the roads). This combination resulted in particularly heavy levels of claims, including complex business interruption claims.

Some policies now include a "climate change" exclusion, which is designed to exclude from the cover all losses arising as a result of "climate change" or "global warming". To date such an exclusion has not been upheld by the courts, who have cited a lack of evidence proving climate change as a proximate cause. Experts have commented, however, that within the next 10 years there is likely to be sufficient data available to support an argument that climate change has directly caused a particular weather phenomenon. Such data will likely thrust this sort of exclusion into the limelight in future.

Until then, however, reinsurers should bear in mind that catastrophe losses are likely to come from unexpected corners, and soft wordings may bite at the unlikeliest of times.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.