Newsletter - The Weather Club

Issue 15 Autumn 2016

theWeather Club Newsletter

Autumn 2016:

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Newsletter Get blown away by theWeather Club

theWeather Club 104 Oxford Road Reading RG1 7LL Tel: 0118 956 8500

Weather Report

Weather news stories from around the world during the last three months

Research News

An update on recent scientific research

Weather Applications

Forecasting for open waters

Weather Watch

Weather Photographer winners announced

World Weather

A traveller’s guide to Trieste, Italy

Science Lesson

Measuring our climate over the years

Weather and Climate view

Paul Hardaker and Ellie Highwood discuss our oceans and being by the sea

My Weather

David Hempleman-Adams writes about the weather around the North Pole

Weather Facts

And finally...

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+ Weather

Welcome Dear Weather Club readers,

Report

September marks the end of meteorological summer, which on reflection was not too bad at all. Despite a stormy start back in June with episodes of localised flash flooding, this was then followed by a hot and dry August, plus a few brief heatwaves, particularly across the southern half of the UK.

UK Weather June 2016

The weather was making headlines not just regarding extreme events, but the announcement of MeteoGroup securing the contract with the BBC after the Met Office’s 94year deal came to an end (page 7).

1981 - 2010

Actual

Anomaly

Average Max

17.8°C

0.5°C

Average Min

10.1°C

1.3°C

Mean Temp

13.9°C

0.9°C

Sunshine

138.0 hrs

81%

Rainfall

101.8 mm

139%

Chloe Moore Author and Editor of theWeather Club Newsletter

The Rio Olympics provided fascinating entertainment with a record number of GB medals, although the weather proved problematic at times. Too rough to row, not enough wind to sail. ‘Sailing to success’ on page 6 talks you through weather on the water, from

the infamous shipping forecast to the resources you can use to create your own forecast. Our ‘World Weather’ feature visits the beautiful, relatively unknown Italian city that is Trieste and our ‘My Weather’ section guides you through the weather in the extreme North Pole. As autumn arrives, the leaves fade and fall to the ground, (and the heating goes on!) I hope you enjoy flicking through this latest edition. RMetSoc

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Olympic Ceremony features UK scientist’s climate spiral With the world watching, Brazil’s Olympic Opening Ceremony was the perfect platform to educate more than three billion viewers about global warming and climate change. Within a bright, booming and creative ceremony, our changing environment was a key feature. A short video on anthropogenic climate change, narrated by Dame Judi Dench, included maps and graphics showing how rapidly the earth’s temperature is rising, the staggering amount of ice that has melted over the last century and how rising sea levels will flood cities around the world in the future. Featured in the video, was a graphic illustrating how global temperatures have risen by more than 1.0°C since 1850. The graphic was almost identical to that produced by Dr Ed Hawkins, climate scientist with NCAS at the University of Reading and RMetS Fellow, that was featured earlier this year on his blog ClimateLabBook and re-tweeted over 15,000 times.

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However, Ed’s twitter revealed he was clueless that the GIF he produced back in May 2016 was being used in the Olympic Ceremony. Despite the shock, he was clearly delighted to see climate change included “It was fantastic that the organisers of the Opening Ceremony chose to highlight the risks of climate change in this way to so many people around the world. It is a truly global issue which will affect all nations and requires strong international collaboration to understand and tackle.”

When asked how the idea for the graphic first came about, Ed explained “For the original GIF, I wanted to try and visualise changes in global temperatures in different ways to learn about how we might improve our communication. The spiral presents the information in a straightforward way which appears to resonate with people.” Since Ed first published the graphic, numerous adaptations have been created to illustrate other climate issues.

Screenshot from coverage of Rio Olympics opening ceremony. (Source: BBC)

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Summer 2016: Heavy rain and hot June - August 2016

Weather Report

Summer began settled and mostly dry, however heavy showers and thunderstorms became a recurring theme for the rest of the June. Warm weather for the first five days gave the maximum temperature of the month with 27.8°C recorded at Porthmadog (Gwynedd) on 5th June. Thousands of flashes of lightning and torrential rain wreaked havoc across southeast England on 23rd June, coinciding with EU Referendum Day (read the full story below). With very wet weather throughout June in Aberdeenshire and heavy thunderstorms across much of England and Wales, UK rainfall was 139% of average. In July, changeable conditions bought breezy and showery weather for the first half of the month with a chilly start for the north on the 2nd, recording a minimum of 0.5°C at Altnaharra (Sutherland). Spells of rain and showers continued for the next two weeks with the arrival of hot and sunny weather from the 18th – 20th. On the 19th July, many weather stations across the southern half of the UK exceeded 30°C, leading to heat-related delays on railways. Cooler, unsettled weather quickly re-established itself further north, with large hailstones (the same diameter as a two-pence piece) on the 20th, as well as a GP surgery receptionist hospitalised after lightning entered the building and struck her chair in Denny, near Edinburgh. Although rainfall was 104% of average, there was a strong north-south contrast. Scotland, Northern Ireland, Cumbria and Snowdonia were generally wetter than average, whereas south Wales and the southern half of England

Spells of fine and dry weather, combined with hot temperatures provided great weather for those staying in the UK this summer (Source: Deposit Photos)

were drier than normal, with less than 5 mm of rain locally in some parts of the far south. The first fortnight in August was unsettled with frequent wet and windy weather. 70.2mm of rain fell at Loch Shiel (Inverness-shire) over a 24-hour period on the 11th and an unusual depression for the time of year bought strong winds to much of England leading to a 69mph wind gust recorded at the Isle of Wight on the 20th. Recurrent southerly winds bought hot weather from the Continent in the latter half of the month, resulting in temperatures exceeding 30°C over south-eastern England. 34.1°C was recorded at Faversham, Kent on 23rd August marking the warmest day of 2016 so far.

Torrential rain and flash floods on EU Referendum Day Torrential downpours and thunderstorms on 22nd and 23rd June, caused episodes of flash flooding across south-eastern England as almost one month's worth of rain fell overnight.

UK Weather July 2016

1981 - 2010

Actual

Anomaly

Average Max

19.2°C

-0.1°C

Average Min

11.4°C

0.5°C

Mean Temp

15.3°C

0.2°C

Sunshine

158.9 hrs

92%

Rainfall

81.2 mm

104%

The vast amounts of rain forecast led to the Met Office issuing an amber weather warning for counties in and around London. South Farnborough, Hampshire, recorded the highest totals with 45.6mm reported over just 14 hours from 22nd June 7pm - 23rd June 9am. St James's Park in London was closely behind with 44.4mm of rain over the same period. Both polling and underground stations in south London were forced to close due to flooding. An influx of water and commuters associated with the evening rush-hour forced London


Lightning over London on 22nd June 2016 (Credit: Paul Townsend, Flickr)

Waterloo to temporarily close with several people tweeting that they would miss the 10pm deadline to cast their ballot. London Fire Brigade attended more than 400 incidents, with calls out to properties struck by lightning and cars submerged underwater. The thunderstorms also led to impressive lightning displays, as captured in the image above.

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Hurricane Hermine strikes Florida

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Weather Report

Hermine was downgraded to post-tropical cyclone status, before briefly strengthening over the northeast Atlantic coast The National Hurricane Center (NHC) first noted the potential for the storm to develop on 18th August and 13 days later on 1st September, Hermine was upgraded to hurricane status after winds exceeded 75mph (120km/h). Despite the storm being widely reported on international media, Hermine was only issued as a Category 1 hurricane (Category 5 is the most destructive). As the hurricane intensified over the northeastern Gulf of Mexico and made landfall, heavy rainfall occurred across western Florida. At Lake Tarpon Canal, an area 100 miles to the southwest of Florida, almost 2ft (568 mm) of rainfall was recorded over 72 hours. Wind gusts

UK Weather August 2016

1981 - 2010

Actual

Anomaly

Average Max

19.7°C

0.6°C

Average Min

11.4°C

0.6°C

Mean Temp

15.5°C

0.6°C

Sunshine

178.8 hrs

110 %

Rainfall

88.4 mm

99 %

Flooding in Florida disrupts transportation (Source: Greg F. Flickr)

exceeding 75mph knocked down trees in northwestern Florida, damaging roofs and power lines, with 325,000 buildings affected which is 1% of all homes and businesses in the state. Shortly after making landfall, the eye of the storm closed and winds weakened to 50mph, with the storm then tracking across Georgia and the Carolinas. This left another 270,000 people without power, and a pecan farm near Ray City, Georgia (approximately 200 miles south of Atlanta) suffered losses of $4 million with 1,000 trees down on site. After reaching the Atlantic Ocean, Hermine transitioned to a post-tropical storm, however the ocean's energy reinvigorated the storm with increased wind speeds and thunderstorms. This coincided with the Labour Day weekend (3rd to 5th September), disrupting events in several states, including beach closures in New Jersey and New York and Amtrak cancelling train services. By 6th September, Hermine weakened as it continued to recede offshore. Early estimates have placed total insurance losses in the USA at $500 million.

Middle East sizzles in 50°C heat

Record temperatures in the first half of 2016 have continued with extreme heat across Asia this summer

Back on 21st July, Mitribah, Kuwait, reported a temperature of 54°C (129.2 F) setting the new highest temperature for Asia, as well as for the entire Eastern hemisphere.

However, before the record is confirmed, the World Meteorological Organisation (WMO) will investigate examining the instrumentation used, the quality of observations and the microclimate of the location. The whole Middle East region experienced unusually high temperatures during a heat wave in mid-July, with the city of Basra, Iraq, reporting 53.9°C on 22nd July. By mid August, temperatures across the Middle East normally dip slightly as the peak of the summer heat is over, with average temperatures over Baghdad hovering around 42°C. However, a second heatwave in late August saw temperatures in Iraq exceed 50°C.

Temperatures hit 54°C in Kuwait in July. (Credit: Molly John, Flickr)

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According to the World Weather and Climate Extremes official archives, the hottest temperature ever recorded on Earth was at Furnace Creek, Death Valley, California, USA at 56.7°C on 10th July 1913.




Dedicated snow spotters monitor climate in the Scottish Highlands Summer for Iain Cameron involves searching for snow in the Scottish highlands. While patches of snow in England and Wales have usually melted by May, in Scotland the patches can be found to survive all summer long. During the winter, huge amounts of snow are deposited and accumulate through wind drifts. In some areas on Ben Nevis, winter snow can accumulate to depths in excess of 20m (75ft). For the last 22 years, Iain has been counting the number of snow patches left on Scottish mountains from the previous winter. Iain works with David Duncan and Adam Watson; a renowned Scottish scientist who also shares a love of snow dating back to the 1940’s. They also rely on a team of walkers and climbers to contribute to the dataset with volunteers logging their own observations and photos using social media and on www.winterhighland.info.

Research News

winter 2015/2016, although they caution that this year’s total is likely to be an underestimate, given that not every location was observed. However, the figures from the August 2015 snow survey were quite different. The total number of patches counted across Scotland last year were 678; more than double the amount from 2014 and hundreds more than any year since the survey was started back in 2008. Iain’s latest expedition was documented by the BBC and featured on both The One Show and Countryfile’s Summer Special in July 2016. Catch up here: www.bbc. co.uk/programmes/b07n3364

The eighth survey took place on 21st and 22nd August. The area covered includes the Nevis range, the Cairngorms, and the Central and northwest Highlands. If possible, the team also try and measure the width and depth of the snow patches using a laser tape measure, with the aim that the data will become useful to those monitoring climate trends. Iain annually publishes his findings in the Royal Meteorological Society’s Weather journal (http:// onlinelibrary.wiley.com/journal/10.1002/(ISSN)14778696) and concludes that 74 snow patches survived until

Every summer, Iain and a team of volunteers count the number of snow patches left on the Scottish Highlands during summer (Source: Iain Cameron, Flickr)

Urban heat island advection shows warming of +1°C

A new network of automatic weather stations is allowing scientists to study our atmosphere at higher resolution than ever before. Around 70% of the world’s population are predicted to live in cities by 2050. These man-made areas are creating ‘Urban Heat Islands’; places where the temperature rises due to changes in the landscape. Cities are unable to cool down as efficiently as their surroundings. This is because buildings cause slower wind speeds and reduce the amount of heat released to the atmosphere at night. Vehicles and buildings also produce heat and pollution, as well as reduced evapotranspiration because of changing land-use with less vegetation.

warming due to the Urban Heat Advection process can cause areas downwind of a city, Birmingham in this case, to be almost 1.2°C warmer. The well-being of city dwellers must be considered by urban planners and risk management teams, as they need to ensure plans are in place that will protect the health of vulnerable populations and critical infrastructure as our cities continue to heat up in the decades ahead.

Although Urban Heat Islands are well researched, few studies have considered how horizontal winds affect the atmospheric processes taking place; a process called Urban Heat Advection (UHA). Research led by Richard Bassett at the University of Birmingham was recently published in the Royal Meteorological Society's Quarterly Journal (DOI: 10.1002/qj.2836). His team found that


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+ Weather Applications Sailing to success Inclement weather disturbed the sailing programme throughout the Rio 2016 Olympics. Andrew Eccleston, meteorologist and lecturer in Nautical Studies explains the forecasting basics before taking to the water. Sailing is a very popular pastime in the UK – and has been especially prominent recently with Team GB’s success at the Rio Olympics and Sir Ben Ainslie’s challenge for the America’s Cup. These racing events are for the professional elite, but sailing can be enjoyed by anyone, on boats of all different sizes – from a dinghy on an inland lake through to cruising the world’s oceans. Whatever kind of sailing you do, one factor in common is – the weather. Sailing boats rely on wind speed and direction and these are critical factors which can affect not just enjoyment when out on the water - but also safety. Trying to sail when the wind is fickle can be frustrating, but setting out to cross the English Channel and encountering an unexpected gale can be a matter of life and death. Therefore

Map of Sea Areas and Coastal Weather Stations referred to in the Shipping Forecast. (Source: Wikipedia)

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sailors require weather forecasts on a variety of scales - from a few hours ahead over a local area, to perhaps several days in advance when crossing an ocean. We are all familiar with the Met Office’s Shipping Forecast – which has achieved ‘national treasure’ status – but this is a relatively basic forecast product, covering quite large areas over long periods of time. There is also an Inshore Waters Forecast which is particularly useful for coastal sailors in UK waters. Both these products are available on the Met Office website and also transmitted by radio in several different ways. However, a sailor who needs more detail, or wants to sail to foreign ports, will need to find other sources of information. The internet provides a huge range of weather data, with many websites specially focused on sailing. A very comprehensive gateway to all this is available here: weather. mailasail.com/Franks-Weather Meteorologists now use NWP (Numerical Weather Prediction) to provide levels of accuracy which have improved significantly in recent decades by using ever bigger and faster computers. For many years NOAA (the USA equivalent of the Met Office) has made the output of their global models freely available on the internet. Many of the websites providing weather forecasts rely on NOAA data and sailors can also download it directly into their navigation systems – perhaps the


Perfect weather at the Panerai Classic Yachts Challenge in September 2014, Imperia, Italy (Source: Paolo Airenti)

ultimate way to combine weather and sailing! If you would like to learn more about ‘Weather and Sailing’, there is a Seminar organised jointly by the Royal Meteorological Society and the Royal Institute of Navigation taking place at the Met Office in Exeter on Saturday 12 November 2016. There is a great line up of speakers, from many different backgrounds – including the Chief Meteorologists from both the Rio Olympics and Sir Ben Ainslie’s team! For more information and registration, go to: www.rmets.org/events/ weather-and-sailing-seminar-2016



+ Weather Watch

Weather Photographer winners announced

More than 800 photographs were entered and over 2,500 members of the public voted for their favourite image. We can now reveal the winners from the Weather Photographer of the Year 2016 competition! Thrilling lightning strikes, twisting tornadoes and stormy seas are just a snapshot of some of the entries that were submitted to the Weather Photographer of the Year 2016 competition. The competition was run jointly between the Royal Meteorological Society and Royal Photographic Society (RPS) and launched back in January 2016. Calls for entries were from two categories: 1) 16 and under, and 2) over-16’s. With more than 800 images entered, this created a challenging task for the selectors to narrow down the best images to be part of the exhibition. Selectors included internationally-known

1st place in the over-16’s category was awarded to Ben Cherry for this shot of 'Sprite lightning', captured off the coast of Costa Rica (Credit: Ben Cherry)

photographer Tim Rudman and BBC weatherman Peter Gibbs. Overall Weather Photographer of the Year 2016 was awarded to Tim Moxon for his photo of 'Tornado on show'. Tim captured the shot whilst storm chasing in Colorado and describes the image as "one of the most photogenic tornadoes of the year". Ben Cherry's image (above) of 'Sprite lightning' won 1st place in the over 16s category. Michael Pritchard from the RPS said Ben "made the most of circumstance and serendipity to capture a very rare form of lightning" and that the photo "...stood out immediately to the selectors.”

Commenting on all 22 of the shortlisted images, Peter Gibbs said ”The pictures take us on a world tour of stunning weather phenomena, from supercell thunderstorms in the US Midwest to Antarctic diamond dust via a mist-shrouded Welsh hillside". The photographs will be on show at exhibitions in the UK later this year and in early 2017. Despite this being only the first year the competition has ran, it’s been a huge success with the call for entries for next year's competition opening in early 2017. For more information and to view all the winning images, visit www.weather-photo.org

BBC picks private weather company The Met Office has provided the data used for BBC weather forecasts for 94 consecutive years, however the contract will soon come to an end, with MeteoGroup taking over from spring 2017. Back in 2015, the Met Office confirmed they had lost the BBC contract. As the BBC is a publicly funded organisation, they are legally required to secure the best value contract, opening up the opportunity for private weather forecasting companies to supply weather services to the world’s leading broadcaster.

The Met Office had provided the data used for BBC forecasts since the corporation’s first radio weather bulletin on 14 November 1922. Despite MeteoGroup replacing the Met Office, a vast majority of their much-loved weather presenters will remain forecasting for BBC Weather. MeteoGroup is the UK’s largest private weather business, with offices in 16 countries around the world. They provide weather services for companies including the National Grid and the majority of companies


who maintain the UK roads network. In terms of media, they already supply the weather for UK Press, Sky and Channel 4 and will take over on the BBC from spring 2017.

Expect new graphics but rest-assured it will be the same faces from spring 2017 on the BBC (Source: BBC)

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+ World Weather A traveller’s guide to Trieste, Italy Expect Mediterranean-style weather in the summer and mild winters in one of Italy's most under-rated cities With almost 50 million visitors each year, Italy is the fifth most visited country in the world, with Rome, Venice and Florence dominating the tourist hot-spot list. You may have not even heard of Trieste, but in a quiet corner of northeastern Italy lies this small, majestic city.

means Trieste’s history and culture has been influenced by Latin, Slavic and Germanic cultures. The topography of Trieste results in an area composed of several different climate zones depending on the distance from the sea and elevation.

In 2012, LonelyPlanet.com listed Trieste as the world's most under-rated travel destination, with other travel guides suggesting the city is unfairly overlooked - not only in Italy, but in all of Europe.

According to the Koppen-Geiger classification, the climate of Trieste is defined as Cfa; a humid subtropical climate with strong Mediterranean influences. The mean annual air temperature for Trieste measured over the period 1951-2011 was 14.1°C.

Trieste is located in northeastern Italy, on a narrow strip of land that runs between the Adriatic sea and Slovenia. It’s close proximity to so many borders

In the spring, the temperature gradually increases, rising by about 10°C over the course of the season. By May, daytime average temperature are

Piazza Unità d'Italia is one of Trieste's most popular landmarks and is one of Europe's largest squares situated beside the sea

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Situated in the far northeast of Italy, Trieste borders both Slovenia and Croatia (Source: LonelyPlanet.com)

21.6°C. Although March is relatively dry with around 65mm of rainfall, by April and May this increases to 80-85mm. Generally, there is a light breeze all year round, ranging from 5-8mph. Although at the start of the spring season the breeze originates from the northeast, shifting to an easterly by the start of the summer. Summers in Trieste are normally fine with clear, sunny skies and high temperatures. Daytime temperatures tend to reach around 25-28°C (7782F), with the temperatures at night cooling to 18-20°C, creating pleasant conditions for remaining outdoors in the evening and dining al fresco. July is the sunniest month with over 9 hours of sunshine each day, on average. Humidity in Trieste remains fairly constant all year round, but is at its lowest in the summer months with typical relative humidity values between 62-65%.



The clear, blue waters of the Adriatic are great for swimming in, or mooring a yacht!

Castle Miramare has stunning panoramic views out on to the Gulf and back towards the city

In autumn, the climate remains warm and mild, with daytime temperatures in September still reaching 23°C on average, although they have peaked at 34.4°C in September in the past. By November, maximum average temperatures are closer to 12°C, however the sea remains relatively warm, making it possible to still swim comfortably in the autumn in the clear, blue waters of the Adriatic.

phenomena affects Trieste. The city is often swept by Bora; a north-easterly to easterly wind blowing downward from the Karst plateau. Each year, gusts in the area often reach 80mph (130km/h), with the strongest gust on record at 111mph. When the Bora wind is strong and persistent and occurs at the same time as freezing temperatures, thick sea-ice can form on the harbour facilities, piers and boats, creating a stunning visual effect that is unusual to observe in the Mediterranean region.

Winters in Trieste are relatively mild compared to other parts of northern Italy. Interestingly, winter is the driest season in Trieste, recording a mean precipitation of 203mm. On average, the temperature only drops below freezing six times per year, although there are generally large variations from year to year. The lowest temperature ever recorded in Trieste was -14.3°C on 11th February 1929. Each winter, a peculiar meteorological

The iconic city centre is Piazza Unità d'Italia; the main square located at the foot of the steeply descending hills, between the large 19th-century avenues and the old medieval city. It is said to be one of Europe’s largest squares that is situated next to the sea. Bars and terraces are dotted around the edge of the square, providing a

picturesque setting to meet friends or look out to the horizon and spot ships at sea. Trieste itself is composed of many narrow and crooked streets with a waterway running through the heart of the city centre. Along here and surrounding side streets lie numerous cafes and ice-cream shops where locals can be found catching up in the street, drinking espressos or grabbing a bite to eat. A short bus ride, or a long walk from town, lies Castle Miramare. This characteristic castle was completed in 1860 and includes 22 hectares of gardens full of a range of botanic species. Given its location on a cliff next to the sea, it provides outstanding panoramic views looking out to sea and back to the city centre. If you want to explore further afield, Trieste offers great connections to travel to other areas of both Italy and Europe. A 3-hour train ride will take you to the romantic city of Venice, less than 20km away is the Slovenian border, or hop on a ferry from Trieste to the northern coast of Croatia. Travelling to this hidden gem of Europe takes just over two hours via air from London. With a comfortable climate, spectacular architecture and the blue waters of the Adriatic, Trieste is a wonderful destination for a short city break or stop-off on a grand European tour. Or, indeed, the latest European Meteorological Society's conference, which was just recently held in Trieste this September.

Climate of Trieste Average minimum temperature: 3.8°C in January Average maximum temperature: 27.9°C in July Average rainfall: 56.9mm in February 111mm in October 1,003mm a year

The effect of the Bora wind in Trieste

Sunshine hours: 83.7 hours in December 288.3 hours in July 2,112.5 hours a year

(Source: Massimo Armani, Flickr)


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+ Science Lesson Measuring meteorological variables for studying the climate The first instrumental weather measurements that have survived started in the 1660s from early thermometers, soon followed by rainfall and snowfall (precipitation) measured using early types of raingauge placed on roofs. Starting in 1659, the longest surface temperature data set is the Central England Temperature (CET) dataset, which is supported with weather diary information. By 1850 weather instruments were widely operated in Europe, the eastern US and some other regions including, sparsely, the oceans. This is when some current global data sets commence. Other global temperature data sets start in 1880 when data became more widespread and the measurement methods more uniform. Until World War II (WWII) most meteorological measurements were made using instruments read by people. After WWII atmospheric measurements up to the lower stratosphere (20km) were made electronically by a set of weather instruments attached to a balloon (known as radiosondes) with the number of these increasing very rapidly. These represent the first quasi-global set of remote measurements. Although originally made mainly for weather forecasting purposes, they provided a great increase in our ability to monitor climate and its variability from the late 1940s. Over land, automatic weather station (AWS) measurements

Map of the land-based long-term monitoring stations included in the Global Historical Climatology Network. Colours indicate the length of the temperature record available at each site. (Source: Wikipedia) started to be introduced in the 1980s, while semi-remote methods were developed for monitoring the depths of the oceans to around 1,000m from the 1940s, though these measurements were not truly global. A large step forward in our ability to monitor climate occurred in the 1970s with the advent of polar orbiting satellites, providing global coverage of our weather. These use infrared or microwave radiation to sample properties of the atmosphere, such as temperature and humidity and the amount of rainfall falling. These data are crucial for weather forecasting, but are now also sometimes used for climate studies where they are often combined with in situ data into amalgamated data sets. Satellites also provide data about the biosphere, including how the land surface is changing, for example whether forests are chopped down for agriculture.

A Met Womens Auxiliary Air Force (WAAF) reads wet and dry bulb thermometers housed in a Stevenson Screen (Source: Met Office)

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A further increase in our ability to measure climate through the depth of the atmosphere, sometimes up to the lower mesosphere (50km), started in the 1990s through the method of “reanalysis”. Here a fixed climate model assimilates diverse observations, including satellite data since the 1970s. Using




advanced statistical methods this technique has been extended recently to allow climate and its changes to be usefully estimated through much of the depth of the troposphere (from the surface up to 20km) back to 1851, long before the advent of radiosondes or satellites. Finally a large step forward in the remote monitoring the climate of oceans occurred in the early twenty first century with the advent of ARGO floats that periodically move up and down through the open oceans. Some 3,000 of these now measure temperature and salinity in the top 2,000m of the oceans worldwide and their impact on our understanding of, and ability to predict climate, has yet to be fully felt. The importance of climate studies has been much increased by recent climate warming and its substantial attribution to human activity1. Thus global mean surface temperatures have increased by about 1°C since the late nineteenth century, and substantially more in the Arctic. 2015 has been the warmest in the instrumental record globally, though it was also influenced by an important mode of climate variability, El Niño. In fact the interaction of human induced climate change and regional natural climate variability is now a key topic, emphasising the need for more detailed regional observations and regional “reanalyses”. The widespread climate changes being observed are consistent with the latest estimates of the enhanced radiative forcing of climate by greenhouse gases since 17502, around 2.9W/m2. Not surprisingly measurements of the geographical distribution of the various

There are more than 3,000 Argo floats globally that measure the temperature and salinity of the ocean. This allows, for the first time, continuous monitoring of the temperature, salinity, and velocity of the upper ocean, with all data being relayed and made publicly available within hours after collection. (Source: Scripps Institution of Oceanography) greenhouse gases using satellites and in situ methods (including carbon dioxide, methane, nitrous oxide and others) has become a key component of climate measurements. In fact the variables discussed in this text and many others are now identified by the Global Climate Observing System3 as “Essential Climate Variables” (ECV). One ECV, ocean subsurface temperature, has become crucial to understanding how the global climate is being warmed by enhanced radiative forcing. Different analyses of ocean heat

content now consistently show that about 90% of this enhanced heating is occurring in the upper global oceans at a rate consistent with the many other prominent and diverse indications of climate change2. These include worldwide glaciers, ice sheets, snow cover, permafrost and sea ice melt, sea level rise, changes in nature and agriculture, warming of lakes and rivers, increases in heat waves and decreases in cold extremes and increases in average and severe precipitation, and atmospheric moisture content.

Notes, further reading and references 1. Intergovernmental Panel on Climate Change, 2014: Climate Change 2013. Cambridge University Press 2. Blunden, J. and D. S. Arndt, Eds., 2015: State of the Climate in 2014. Bull. Amer. Meteor. Soc., 96, S1– S267. 3. GCOS 2010: Implementation plan for the global observing system for climate in support of the UNFCCC (2010 Update). GCOS-138. World Meteorological Organization, 180 pp. http://www.wmo.int/pages/prog/gcos/Publications/gcos-138.pdf • Strangeways, I. C., 2003: Measuring the Natural Environment (Second edition) Cambridge University Press. • 30-Second Meteorology, 2016: Ed: A. A. Scaife, Foreword, J. Slingo. Ivy Press, pp 160. The Royal Meteorological Society would like to thank Chris Folland, Phil Jones and Victor Venema for reviewing the paper. Also, thank you to members of the Climate Science Communications Group including Peter Stott and Ian Strangeways for all their efforts and hard work in bringing this paper together.


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+ Weather View

Prof Paul Hardaker Chief Executive of The Institute of Physics

Water, water, everywhere In my newspaper this morning (I haven’t yet gone digital largely because of the crossword) I read an article about how the most of the happiest places to live in the UK are on the coast – interestingly that excluded London! I lived by the coast myself for 3 years and can see the attraction. We are an island (or a group of islands to be more precise) after all and the UK’s connection with the sea is long and fascinating. In fact the first weather forecasts were born out of Admiral FitzRoy’s vision for a warning system that would bring a step change in safety of life for those at sea, and ultimately led to the founding of the Met Office. Stepping up in scale for a moment, when I was at school the only planets we knew about were in our solar system. Now we have discovered a few thousand and we are still counting. I find that astonishing and feel certain that we will find life away from earth in the next decade. One of the important factors in that is water and on earth we have plenty of it. In fact about 71% or so of the planet’s surface is covered by the oceans and that accounts for about 97% of the water on our planet. Nothing does that more justice than NASA’s iconic blue marble photograph which gives a real sense of the scale of the earth’s great ocean basins. Although, interestingly, water only accounts for about 0.05% of the earth’s mass. It’s still not really understood how our oceans have come about and how water accumulated on the earth over the past 4.5 billion years. It has been suggested that some of the water was transported to earth by comets and proto-planets that formed in the asteroid belt and which smashed in to earth. But studies of the moon suggest that there could well have been a more dominant source, and that water may have already been present in the materials that formed the early evolution of the earth. Later this

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water has leaked out from the rocks and minerals to make up our planet’s oceans. But that’s not the end of the story. Hydrogen and its isotopes are being lost back into space, and the estimate is that about one-quarter of the original mass of the oceans has already left the planet. The name ocean has a Greek origin, of course, and comes from Oceanus who was one of the Titans, who preceded the Greek gods. Oceanus was the personification of the great river that encircled the earth. You might have seen the statue of Oceanus, it sits as the centre-piece of the Trevi fountain in Rome. Although we often think of our oceans as separate basins, it is true that it’s one connected global ocean and it was the Russian oceanographer Yuly Shokalsky who coined the term ‘World Ocean’. We now know that there is more to this connection than simply having a navigable route. The water moves through this World Ocean by the thermohaline circulation (thermo referring to temperature and haline the salinity) in what is often called a conveyor belt. The temperature and salinity differences form a density gradient, which is what in practice drives the circulation. There are lots of estimates of transit times for water around this global circulation, with estimates between 500 to 1,000 years. It’s quite something to think that Atlantic waters around the UK today were last there when King Canute was trying to halt the incoming tide.

just as interestingly is the role that it plays in mixing the water characteristics between ocean basins. With all this energy and momentum the oceans are a real engine room for our climate, but also hugely important for weather forecasts on monthly and seasonal timescales. Much of the improvement that we have seen in these forecasts over the last few decades have come from meteorologists and physical oceanographers working together to build combined models of the atmosphere and the oceans. The other important development is our improved observations of the oceans, both from satellites and from ocean buoys. Satellite observations are very important and can cover wide areas, but they cannot observe down in to the oceans and so we still need in situ observations. The Argo programme is one particular success story with 30 countries working together to strategically deploy over 3,000 buoys across our oceans to measure temperature, salinity and currents. The Argo floats as they are known, drift at a kilometre below the surface and every 10 days dive first to 2km and then up to the sea surface to transmit their data back via satellites. It is through observations like these that we can unravel the complexities of our oceans, which in some areas are the least well explored parts of our planet.

Movement of the water also transports energy and mass around the globe, but

With all of this technology I still enjoy reading less scientific descriptions of our oceans like this from Samuel Taylor Coleridge’s Rime of the Ancient Mariner:

Water, water, every where, And all the boards did shrink; Water, water, every where, Nor any drop to drink.

About, about, in reel and rout The death-fires danced at night; The water, like a witch’s oils, Burnt green, and blue and white.

The very deep did rot: O Christ! That ever this should be! Yea, slimy things did crawl with legs Upon the slimy sea.

And some in dreams assured were Of the Spirit that plagued us so; Nine fathom deep he had followed us From the land of mist and snow.




+ Climate View

Prof Ellie Highwood Professor of Climate Physics at the University of Reading

Ships of opportunity The weather is clearly important for water sports and sailing. One only had to watch the Rio Olympics to note days when it was too rough for the rowing or two calm for the sailing. Understanding climate is also important for sailing – premotor power the climatological wind patterns basically determined where, and when you could sail. However, it is less well known how important sailing, and indeed sea vessels in general have been in contributing to our understanding of weather and climate.

USCGC Northland Served on the Bering Sea patrol, and later patrolled Greenland during WW2 (Source: OldWeather.org)

“...our seas and oceans play a major role in driving the climate system. This means we need to know a lot about them”

The moderate to slow timescale response of the Earth’s climate system is dominated by the thermodynamic characteristics of the oceans and their currents. The specific heat capacity of these large bodies of water is large, that is, it takes a lot of energy to raise the temperature of a litre of water than it would to raise the temperature of a litre of soil (or indeed air) by the same amount. Oceans therefore take a long time to warm up and cool down and the resultant changes in ice cover and circulation have a large effect on long term climate change. However, changes in temperature of parts of the ocean happen on much shorter timescales, such as the warming of the mid and eastern Pacific during an El Niño event, and these influence circulation patterns in the atmosphere altering areas of rainfall and drought. On an even more noticeable level, the sea around the British Isles is likely to be cooler on a hot June day than on a moderate September day, since the ocean is still warming up from a summer of extra sunshine. Open ocean swimming is probably best saved until later in the summer – at least from a temperature point of view. So our seas and oceans play a major role in driving the climate system. This means we need to know a lot about them. But it’s hard to measure these remote and challenging regions of the planet. The earliest measurements of sea surface temperature were made by hauling a bucket of sea water on to deck and using a standard mercury thermometer. Wooden buckets used by sailing ships proved to be hazardous on steamships – bouncing along the surface of the water. Canvas buckets made way for insulated buckets, then increasingly engine intake measurements (vast quantities of water


Help scientists recover worldwide weather observations recorded in ship’s logs since the mid-19th century (Source: OldWeather.org)

being needed to cool the engines) and more recently hull contact sensors. Nowadays we can combine satellite products with drifting and moored instrumented buoys but ships of opportunity still play a role. Perhaps measurements of sea surface temperature is the most obvious way maritime pursuits contribute to our understanding of weather and climate, but in the past, they have provided valuable records of weather via their ships logs – a feature recently being explored by the Old Weather project. Old Weather is a citizen science project whereby members of the public can help by digitising old ship log books and other handwritten sources. Not only is this a fascinating thing to do, but the data is being included in state of the art data sets used by climate centres around the world. These logs capture the after effects of volcanic eruptions and storms as well as vital day to day observations of the sea and sky. So, whether you have the latest sensors and technology or just a notepad, a request to all today’s sailors: please keep records of the weather and sea conditions – you never know how the scientists of the future will be able to use them!

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+ My Weather David Hempleman-Adams, British adventurer David leads the crew of voyagers and seafarers on the Polar Ocean Challenge. His team are sailing around the North Pole to draw attention to the issues surrounding the changing Arctic landscape. The Polar Ocean Challenge is led by myself and is a call to the world to navigate the Future of the Arctic Responsibly. The reality we are facing is that irreversible changes in Arctic sea ice seem inevitable. This is already having global economic, political, social and environmental implications with a significant change in my lifetime, with the next generation who we have to think about. In an attempt to provide clarity of these issues, I have set up an education-based charity called Wicked Weather Watch; engaging with schools on climate change and global warming notably in the

Arctic area and using the Polar Ocean Challenge to help launch the early stages. The crew also includes a 14 year old schoolboy, Ben Edwards, who will become the youngest person to circumnavigate the North Pole if the voyage is successful. The day before setting off, 19 th July 2016, all of the ice charts from Russia, Canada and the USA show we can get around across the Barents Sea and across the Kara Sea, but then we hit the ice. In 10 days’ time will it have retreated? It’s all unknown! If we leave until our path is free of ice, then will we have enough time to get through the North West pass before it refreezes and get down the coast of Greenland and across the North

David Hempleman-Adams Atlantic before the winter storms chase us home? The morning of departure, the weather is lovely and everything is stowed. One common theme here is whatever the ice maps show, can all change incredibly quickly if we get a southerly wind for a couple of days blowing the pack ice offshore. So welcome home sea sickness, no change of clothes, wet watches, sleeping in a tumble drier and the smell of adventure. After a hive of activity we left Murmansk.

The NorthAbout ship, captured by the team’s drone

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On day 5, I checked the new ice charts on www.nsra.ru. We still have no chance of getting through yet, not past the cape or through the Laptev



Sea. Nikolai, our Russian Captain who is very familiar with this route, informs me that this is a very unusual year and normally clear. Writing on the 28th July; the last couple of days have been interesting. The great thing about modern weather charts is you can forecast what’s going to happen and we knew we were in for a couple of days of stormy weather. The autopilot was struggling because of the magnetic strength, but also the sea state. The waves grew and we had a beaufort 7/8, which was testing. So we all took it in turns to helm. The crew were brilliant. Some say they were petrified, but still got on the helm. By the end of July, the water temperature is now under five degrees, so you don’t want to fall in! 11 days into our expedition, and I saw our first ice today on my watch, just an hour ago. What is slightly worrying, it didn’t show up on the radar. I think we will see a lot more of that before the trip is out. After several days of delays, the team are back sailing the seas. By 11th August, the water temperature is now -0.3°C. Tonight there was a great ray of sun on the low hills on the shore, with rolling fog on the ice at sea. Very odd combinations, that Turner would have marvelled at. The next day, we had to turn round from the ice by the coast last night and find somewhere safe to anchor. There were strong winds so we needed to find somewhere else to sit them out, and the answer was a stamukha; an iceberg that is touching the bottom. On the 13th August, we have had to go and find shelter. A huge storm is on the way, and high wind, in shallow waters with masses of ice driving your way, is no place to hang around to see what might happen. So, now at anchor, all tired, excited after today, and looking forward to the next hurdle – I think! As I write, the wind is gusting 30 knots, so clever to run for shelter. Writing on 15th August: Well as predicted, we had our storm. It

The progress of ‘Northabout’ and crew since embarking on the Polar Ocean Challenge as of 1st September doesn’t matter where you are in the world, in a tent, or a sail boat, it can be scary, as you are at the mercy of mother nature. Last night was scary for lots of reasons. Very high winds, but shallow waters of 5 meters. So the waves of course were even more exaggerated, and put extra strain on the anchor and chain. The winds slowly rose, past the predicted Grib forecast, and in my experience of 35 years in the Arctic, was the strongest winds I have experienced. I was extremely pleased we didn’t try and anchor at our high point by the beach yesterday, or try and find another Stamukha.

26th August was a great day. We finally passed that elusive line on the charts 180 Longitude. Now we are finally slowly on our way back home. On this leg, we have passed through the Barents Sea, Kara Sea, Laptev Sea, into the East Siberian Sea and now the Chukchi Sea; Its renowned for its wild weather and seas. We are due more high winds but our waypoint is now straight for Point Barrow. We are privileged to witness this magical kingdom. This is why we explore. On 13th September, the team succesfully completed their quest. Find out more on the website: www.polarocean.co.uk/ships-logs

The moment when the crew got through the ice approaching Ostrov Andreya


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+ Weather Facts Sprite lightning an electrical phenomenon that occurs above active thunderstorms (altitudes >50km)

Halo a ring of light around the sun or moon produced as light travels through a different medium

Mammatus clouds are interesting because they are formed by sinking air, as opposed to most clouds that are formed by rising air

Autumn Equinox falls on 22nd September 2016 and marks when the length of day and night are nearly equal

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