Perhaps it is just that having written a novel about climate change and spoken to many scientists about the subject I am tuned in to this, but over the past year-or-so it has been interesting to notice a few examples of ways in which meteorological maps — and the way that weather events are discussed — might be changing. In addition of course to the terrifying new terminologies that relate to emerging behaviours of water and water vapour in a warmer world: ‘atmospheric rivers’ for instance.

First of all at the beginning of 2013, the Australian Bureau of Meteorology’s interactive weather charts needed to have new colours added. The previous temperature range ran through red and burnt orange to black, but had been capped at 50°. Once temperatures started to go above 50° two further categories — deep purple and pink — needed to be added in order to increase the range to accommodate possible temperatures of up to 54°.

(This in a country with — currently — a right wing, climate change-denying and migrants’ human rights-busting government who are currently embarking upon what appears to be an ill-considered dash to cash in some of the continent’s vast remaining coal reserves while they still can. Of course the UK is currently embarking on its own dash for last-ditch, dirty carbon in the shape of fracking.)

Here one hears the word ‘unprecedented’ being used a lot. The series of winter storms that have been battering the country since the so-called St Jude’s storm of 28 October 2013 (which then gave way to a particularly intense spell that has lasted so far from December to the time of writing) is described as unprecedented, as are the severity of individual storm events and their effects; the floods in Somerset; the washing-away of key infrastructure at Dawlish in Devon. All are tagged as ‘unprecedented’, for the moment at least. I’ve mentioned here previously that on Christmas Eve the UK Shipping Forecast announcer on BBC Radio 4 broke out of the forecast’s usual highly-codified language (‘Variable 4, becoming southeast 5 to 7, occasionally gale 8 later’) into a more conversational register to note the presence of ‘a massive area of low pressure of almost unprecedented depth’.

The BBC TV weather forecasts use the traditional, presenter-led format to show e.g. blue areas of rain moving across a simplified geographical map of the UK. These might then cut away to animations of white arrows that show wind direction and speed over the same map.

A simpler BBC weather map and icon system — adapted and little-changed from that developed on BBC TV in the mid-1970s — is currently used for online applications, and this shows a familiar range of stylized clouds, raindrops, temperature indicators etc. A new symbol was recently introduced on these maps. Nothing to do with extreme weather events, but a grey crescent showing predicted distribution of clear or partially-clear skies! The British Isles are usually shown centre-screen — against a white ground or surrounded by a moat-like sea. Only very occasionally does the viewpoint ‘pull-back’ to show where the weather is coming from.

I wonder if an incidental, cumulative effect of the adherence to these conventions is an impression of familiarity and stasis, of business as usual. Whether the apparent isolation of how the British Isles are depicted, together with the sense of visual comfort, contributes to the way that every extreme event feels like a surprise, or is treated like one. Perhaps it is time to change the conversation about weather.

I say this partly because in recent days I have been following the output of the National Weather Service — a US equivalent of the UK’s Met Office — part of the US National Oceanic and Atmospheric Administration which comes under the umbrella (sorry) of the US Department of Commerce. They have also been reporting on the storms hitting the UK, but (obviously) in a non-UK-centric manner: simply in as far as these are events that are happening in the Eastern Atlantic. Interestingly, the NWS use a much stronger vocabulary, e.g. highlighting ‘hurricane force’ winds where these occur, and a completely different — much less comfortable — visual language to describe these storms. The visual material feels very rough and ready, unfamiliar, and not just because the British Isles are marginal. The National Weather Service’s Twitter account (@NWSOPC) also collides different kinds of information and levels of resolution — satellite imagery, air pressure, windspeed and significant wave height — into crude, animated GIFs that are strangely compelling.

At time of writing the latest from @NWSOPC is another GIF of the storm that is currently approaching the UK. Here’s the screengrab they tweeted with the link.

Together with today’s Shipping Forecast (which is also published daily in text or printable form by the Met Office) this makes me glad that I am not at sea. While the UK Shipping Forecast is delivered in a very familiar, litanic style, even this measured and conservative medium is nonetheless capable of surprises — and even when it doesn’t stray from the highly abbreviated convention. Here is today’s forecast (7 February 2014) for the sea area Shannon:

South, becoming cyclonic then west, 7 to severe gale 9, increasing storm 10 or violent storm 11 later. Rough or very rough, becoming very high or phenomenal [my emphasis]. Rain or showers. Good, occasionally poor

I don’t know if I’ve heard the word ‘phenomenal’ used to describe wave height before, so I had to look it up. The designation comes from the Douglas Sea Scale (a.k.a. the International Sea and Swell Scale). By this measure the term ‘phenomenal’ is the top of the scale, used to describe a wave height of over 14 metres. The (perhaps more sophisticated?) Significant Wave Height formulation, which draws on satellite data to generate probable ranges, may render this question obsolete, but thinking back to that recalibration of temperature that was needed in Australian charts a year ago, the addition of purple and pink in response to temperatures going ‘off the scale’, I wonder whether the increasingly extreme weather that is predicted to be caused by climate change might mean that further degrees of wave height would need to be added to the Douglas Sea Scale. ‘Unprecedented’ is already being overused, so what happens when the extraordinary becomes ordinary? What do you call something greater than phenomenal?

§

Click here to see dozens of examples of the evolution in styles and formats of BBC Weather forecasts from the 1950s to the present, on the fascinating TV Ark website.

Download Shackleton’s Man Goes South free and DRM-free from the Science Museum website.