The August 2003 heatwave. The hottest topic of conversation

On Sunday 10 August, not only was the UK highest temperature record broken, but within a couple of hours the mercury reached 100°F.

Bookmakers William Hill cut their odds for people gambling on a new record being set and temperatures reaching 100°F as more people placed bets and the heat wave continued into its second week, but they still faced paying out on both bets. Graham Sharpe, spokesman for William Hill, said "We paid out around £10,000 on the UK temperature being beaten and around ten times that on the 100°F being reached."

Journalists worked overtime collecting heat related facts and figures connected with the heat wave. The Daily Mail (Wednesday 6 August) reported that should 100°F be reached golf balls would travel 5% further than at 50F and that the Forth Rail Bridge would expand to be eight inches longer than its winter length. They even quoted the Prince of Wales, who during a visit to a factory in Glasgow was reported to have said that it was "bloody hot".

With people keen to enjoy the heat, the number of unauthorised absences from work were reported to be high. The Daily Mail (Monday 11 August) reported that they were costing the economy £10 million a day and that so many people were heading for beaches that seven mile tailbacks built up around Bournemouth as people arrived as early as 6am to set up camp for the day.

All sectors put out press releases in response to the high temperatures with the after effects lasting weeks after the heat wave ended:

4 August 2003 Network Rail
"Network Rail today imposed precautionary heat related speed restrictions across some of its network to ensure the delivery of a safe railway" as rail speed restrictions are reduced to 60mph.

5 August 2003 Department of Health
"Ten tips for surviving Summer sun" compiled to "help people keep cool and avoid heat related illnesses".

5 August 2003 British Gas
Customers are asked "to do the unthinkable this week - turn on their central heating" to prevent boiler problems when the weather gets colder.

5 August 2003 Met Office
Businesses use advance forecasts to stock up on 'key Summer goods'. As a result it is reported that Safeways sold 800% more burgers, 700% more iceberg lettuces and 400% more sun cream.

5 August 2003 B&Q
B&Q also benefited from long-range weather forecasts after buyers brought in a new range of outdoor equipment. They reported that sales of swimming pools increased by 300% over the previous weekend, and air conditioning units and fan sales increased up to 200%.

8 August 2003 National Society for Clean Air
Air pollution reached record levels in parts of the UK and after stocking up on record levels of BBQ goods in supermarkets, people were asked to "think twice before sparking up the BBQ" as the smoke from them contributes to poor air quality.

12 August 2003 Met Office
The Met Office's initiative 'Forecasting the Nation's Health' gave hospitals advance warning of the heat wave to help them plan the use of their resources.

Marie Mulrennan, Operations Centre Manager, Addenbrookes NHS Trust said:
"The impact of hot weather at Addenbrookes has been that emergency admissions overall have remained high. During this period the number of stroke and cardiac patients has been higher. We've also seen an increase in the number of evening and night time asthma admissions."
Dr William Bird, Met Office Medical Consultant, said that "it is not the peaking temperatures, but the persistence of these high temperatures that is causing the problem." "Consistent high day time and night time temperatures have a cumulative effect on the body."

18 August 2003 Churchill Insurance
Churchill issued a press release 'Lightning Strikes On The Rise Due To Tropical Weather' to inform people that "lightning could well strike your home more than twice this Summer" with July and August on average seeing about two thirds of their annual claims for damage by lightning strikes.

28 August 2003 WHSmith
In a press release ahead of its year end, WHSmith say that "like for like sales in the High Street business will be flat due to a highly competitive sales environment and the recent hot weather".

28 August 2003 Scottish and Newcastle Brewers
At the Annual General Meeting, the brewers announce that "since May, beer markets in most of Western Europe have been aided by hot and dry weather which has boosted seasonal demand."

1 September 2003 Royal Horticultural Society
Helen Bostock, Horticultural Advisor at the RHS, said "many plants have been affected by the unusual weather patterns this year. We have been inundated with calls about unseasonable behaviour. In many cases the plant will readjust itself as the autumn sets in. This is especially true of drought-stressed lawns and trees showing premature leaf drop in the dry weather."

3 September 2003 Thames Water
The week before the highest UK temperature record was broken put "unprecedented demand on Thames Water". They said that on Wednesday 6 August "the company supplied 2603 million litres to London, the highest for eight years, 300 million litres above average." Although it was the 13th Summer in the region without a hosepipe ban.

The heat wave had far reaching effects on the environment and the economy of the UK. One group of people whose livelihood has been favourably affected was vineyard owners.

Chris White, General Manager of Denbies Vineyard in Dorking, Surrey, said that the year looked set to be the best ever vintage "with high yields and fantastic quality". The mild spring meant that the crops were left undamaged by frost and the dry weather to follow provided a fantastic Summer ripening period. They also planned to harvest at least a fortnight early.

Another area benefiting is the weather derivatives market. Cindy Dawes, Managing Director of WeatherXchange, said "we certainly have had many enquiries as people are beginning to realise that the increasing volatility of weather will mean that their business is just as easily badly negatively impacted as positively impacted and to a point which is unsustainable."

The question on everyone's lips, and in almost all media coverage, was 'is this a sure sign of climate change?'

Simon Brown, Climate Extremes Research Manager at the Hadley Centre, said that it is not an indication that climate change is happening as extreme events will occur even in a non-changing or stationary climate. "However, many climate models are showing UK Summer temperatures are expected to increase and what we currently call heat waves will become more frequent and the hottest of these will become hotter. So the August event can be said to be consistent with a warming climate."

Simon was keen to stress that there are uncertainties in the model forecasts, with other models giving different predictions. The model also assumes that there is no change in global carbon emissions, so greenhouse gas concentrations will rise steeply.

So for anyone else who tried to buy a fan on the hottest day on record in central London, only to be told that the Autumn and Winter line was now in stock, the outlook is not good. It is probably wise to invest in a fan or air-conditioning, just in case.