Subject to funding and interest, Terra Byke will be using peddle cycles to collect air quality & atmospheric composition data. To make this service beneficial to cycle outlets, we have a few other services that you may be interested in. If so, please get in touch with me by email: admin@terrabyke.com

I’d like to say a BIG thank you to all those who have already completed my short survey. Your responses are invaluable in initiating the Terra Byke service.

Here are some of the benefits for cycle hire hubs …

• Helping to keep track of cyclists for theft and break-down cycle calls. Terra Byke will provide position data for each bicycle in the hire fleet, using an augmented GPS signal. Any cyclists in trouble, with unfixable punctures or in urgent need of service, will be quickly identified when they call base.

• Payment to maintain cycle fleet. If one of Terra Byke’s sensor housings becomes damaged in any way, we may instruct the hire hub to fix it themselves. If they choose to undertake this maintenance work, we will pay them ~£20 per hour. Why? To cut down on our call-out fees for an engineer.

• Public engagement and media exposure. If we choose your cycle hub to participate in our pilot study, we’d like to take it to the press! We’d also like to organise climate awareness campaigns and road-show events at your venue to promote our service. We will work with each hub in the marketing / advertising campaigns for these events to attract as many enthusiasts as possible.

• E-learning / Hands-on visualisations. As part of our service, we’d like to provide access to our data visualisations. We’d also like to provide cyclists with a certificate / hand-out, which informs them about their mileage and average speed etc. We’d fully fund these services in return for advertisements for our service.

• We’ll also be considering incentives for wet weather cycling – as Terra Byke is particularly keen on gathering atmospheric data under cloudy skies!

*Subject to approval and funding

In order to assess the quality of data from each cycle hire hub, I’d be grateful if you would take part in my short (10 question) survey,

by following this link to “Survey Monkey”

Please follow me on Twitter:

Project Manager (Weather Logistics UK)

Terra Byke Service – UK & Ireland

Tel. +44(0)7949187732

admin@terrabyke.com

www.terrabyke.com/TerraByke/

Our Terra Byke service strives to undertake in-situ measurements and assimilate ground level atmospheric composition on hourly, seasonal and yearly timescales for a diverse range of rural environments. The Terra Byke sensor system is a brand new project in the pipe-line, under development by Weather Logistics UK. The network will provide Earth Observation (EO) data of rural atmosphere composition and of diverse ecosystems.

The objective of the Terra Byke ground-based Earth Observation (EO) system is to disseminate knowledge and to improve understanding of global change. In addition we hope to promote good health, carbon neutral transport, appreciation of our natural environment and delicate ecosystems, and to encourage the development of a diverse range of off-road cycling routes. We hope to work closely with the UK cycling networks, sponsors, the UK government DEFRA and EO data specialists to enhance the scientific understanding of several geochemical cycles.

The Terra Byke project offers a deeper public insight into the impact of humans on our natural environment. This is acheived by the use of e-learning material and visualisation of end-to-end data. Since the EO data that is gathered by the user (a recreational cyclist) is visualised directly at a base station, a sense of community and engagement and learning is aquired that is not possible using external data.

If you would like to get involved in the knowledge transfer either acting as an events coordinator for knowledge transfer into climate change or for ecological awareness please contact me. Our Terra Byke project requires several representatives that can disseminate information about our project and its applications in road-shows, science fairs and youth earth observation projects. Please contact me using this information form

Since our network is mobile, we have much smaller installation costs than traditional environmental monitoring stations. As a result, qualifying cycle hire stores who register for the opt-in system will be provided with a free set of devices to be installed and serviced on their cycle fleet. They will benefit from on-site learning portals or access to online subscriptions to our data visualization centre, in addition to opportunities for exciting projects / special on-site events with the public. We hope that these hands-on / interactive learning centres will be engaging and will enhance public understanding of climate change and atmospheric science. The four key areas of benefits of our Terra Byke project comprise:

• Climate Change Awareness Campaigns
• E-learning Tools for Education
• Validation with other Remotely Sensed Data
• Improved Scientific Understanding of Biogeochemical Cycles in Diverse Rural Ecosystems
• Promoting Health and Fitness

Please follow me on Twitter @TerraBykeLtd

I can also be found on Facebook!

Weather Logistics UK predicts close to average winter temperatures, but a stormy polar maritime air flow will add a raw "real-feel" factor

As November draws to a close, the weather pattern is beginning to show signs of a major change. A strong cold temperature anomaly in the mid-Atlantic is building as our polar jet stream is being flung northward along the southwest of Greenland. Intense storms and flooding have affected many parts of northern England and Scotland, with the cool and wet weather expected to continue into December. By Christmas it is likely that our weather will return to more changeable and milder conditions, with wintry showers largely confined to the north. Our last weblog article gives some insight into what is causing this wacky weather, however this article presents our latest long-range outlook of what this winter has in store …

Abstract from our Kindle Weather Forecast for Winter 2011 to 2012  -

Includes 2/9 pages – The full document comprises of weather graphics for several regions of the United Kingdom & Ireland and is available to Purchase.

It will be available from 16:00 BST on 1^st December.

Valid from: 1^st December until 29^th February 2011
Issued: 30th November, 2011 (Final Edition)

Blocking Index: 7.3/10.0 (upper third on Atlantic blocking index)

During the course of November, major blocking patterns have been observed over north-west Europe, located between a two-way diverted jet stream. The increased southerly component of airflow relative to north has seen temperatures climb well above average for many parts of the UK and Ireland. In our previous forecast we anticipated the weather to swing into a more negative NAO phase, with an increased prevalence of cold weather blocking patterns. Although this cold transition has not yet been observed in November, the formation of a strong warm dipole either side of the North Atlantic indicates a change toward intense blocking features over the mid-Atlantic Ocean. The northerly placement of the polar jet stream located southward of Greenland is beginning to spin-up deep and compact low pressure systems that have stormed into Scotland and Northern England. This north-westerly polar airflow is expected to dominate the scene for at least the first half of the winter period, with brief Arctic blasts bringing wintry showers to the north and the exposed coastlines. The long-range forecasts indicate that snowfall is likely in England during the middle of December, with a biting northerly wind-chill.

The current atmospheric signal also indicates that we are in an active period of cyclonic activity, although the tendency toward north-westerlies will bring a distinct chill factor and with temperatures typically around the long-term average. Night time frosts are likely to be infrequent throughout the early part of the winter, due to high winds and increased cloud cover.

General Overview:

During the winter 2011-12 season, temperatures are likely to be close to average for much of the United Kingdom and Republic of Ireland with an anomaly of +0.2 ± 1.5°C (+0.4 ± 2.6°F). Much of this warm anomaly is due to a strong climate signal in the North-west Atlantic Ocean, whilst a cold dipole in the mid-Atlantic Ocean is indicative of a distant and strong blocking pattern with cold north-westerly winds. The energy required for heating a household or work-place is likely to be below average with an anomaly of -2 ± 13%, indicating less heating demand than during the inter-annual winter average spanning the years 1961 – 1990. Since land surface temperatures have slowly been increasing over the British Isles over the past few decades, this represents a cool winter (1 in 3) compared to the base period of 2005 to 2010. A combination of above average storminess and higher temperatures indicate close to average snow day events across much the UK and Ireland, with an anomaly of -1%. These calculations were achieved using the SnowCast predictions at Weather Logistics UK

Near-average precipitation is likely to be experienced this winter across all counties. Precipitation anomalies are likely to be around 104 ± 22% (with precipitation events +2% above average). Although there is a great deal of uncertainty at this stage, the North Atlantic Oscillation (NAO) is generally expected to be negative later in the season, giving rise to some severe cold at times. At present, the predictions are based on a cautious estimate of a slightly positive index of +0.5, based on NOAA data from the last two months and the trend toward Arctic weather by mid-December. Cold and wintry events are more likely to affect the exposed coasts of the UK and Scotland during the early season, as brisk periods of Arctic airflow take the bite. Easterly winds may develop later in the winter, as the NAO tends to become more negative and if the mid-Atlantic cold anomaly in sea temperatures strengthens further.

In summary: Signals are in favour of a typical winter, with temperatures and rainfall close to average for many parts of the UK and the Republic of Ireland. There is a strong possibility of Arctic winds or easterly winds dominating the season throughout the British Isles, particularly over Eastern counties of England and Scotland if the long term weather swings to strongly negative NAO indices during the early to mid-season period.

Updates from last month …

Since our last forecast there has been an incremental rise in the predicted NAO from +0.3 to +0.5 that acts to strengthen the north-south trend of temperature and rainfall. The blocking index, based on the most likely positions and intensities of high pressures is similar, but with strong blocking patterns more likely to appear over the mid-Atlantic Ocean at 25°W. North Atlantic Ocean sea temperature anomalies have undergone a significant transition from last month, again confirming that blocking patterns in the mid-Atlantic are very likely. Due to an intensification of the jet stream at the southerly tip of Greenland a strong polar maritime theme will dominate the weather with frequent and heavy wintry showers in Northern England and Scotland. Stormy conditions are also expected for much of the United Kingdom as the weather systems converge downstream. The British Isles temperature anomaly has fallen by 0.8°C to +0.2°C, aided by the tendency toward north-westerly airflow and falling SST anomalies in line with a well established La Nińa. The weather is likely to remain changeable during the winter period, but with extreme periods of cold and snow likely at times as the winds swings toward the north in several sharp Arctic blasts. This is the final update of the winter and supersedes any previous seasonal forecasts.

A Heating Degree Day (HDD) forecast for winter can also be found on our website. To predict your heating energy demand for gas, oil or electricity please view our Weather Media information pages, where you can also find a download link for our free UK climate calculator.

Further contact details …

e. forecasts@weatherlogistics.com ; m. 07949187732

An array of blocking high and low pressures are teleconnected in the northern hemisphere. These winds are diverting the usual course of the low pressure systems at the surface.

Golden leaves fluttering from our wooded oaks, bramble bushes in full bloom, tomatoes flourishing under cover – yet not the typical weather we might expect in Britain during late November. The outdoors play with our perception of flowing time, our shopping behaviour, the very psychology of Christmas decorations – with the weather almost forgetting to prompt us with those crisp frosts and the odd snow flakes that spark our seasonal imaginations. So as we approach the advent month, and as Weather Logistics UK approaches an end to its operational weather forecasting, we investigate the deeper goings on in the atmosphere that are responsible for these little quirks of nature. After two winters of extreme cold and snow, we address the question of what is causing our unseasonable weather …

Intense blocking patterns located over Poland and the northwest Pacific Ocean have played havoc with our seasonal weather, driving southerly rivers of warm air into Britain and the southeast of the US. This wacky weather phenomenon has seen temperatures in England soar into the high teens during November. In a sense the east coast of the US and the UK are often teleconnected in their seasonal weather, as broadly speaking the planetary waves that are spun-out by our Earth’s rotation operate in their most stable state with a 60 to 70 degree wavelength. So it’s rather unsurprising that our northern hemisphere jet stream has deflected wildly northward at both longitudes, rather like two rather aggressive slinky shaker partners.

Yet as the jet stream flings northward, there have been equal arguments in the northwest America where the vigorous north Pacific upper air flow has plunged far south. This has resulted in unseasoned cold and winter storms that have sent soggy shivers across the northwest, with snow reported in parts of California much earlier than the seasonal norm. Meanwhile, short and sharp Arctic bites are expected across the East Coast of America this season. In part, this is due to the prevalence of relatively cooler surface waters over the tropical Pacific that is associated with a La Niña. A deep cold snap over the East coast of the US points toward an abrupt and intense Arctic-type weather scenario in the UK in 14 to 21 days time. This Arctic deep freeze will see temperatures plummet, with significant widespread snowfall and perhaps blizzard conditions across Britain during mid-December 2011.

The good news, is that our resident high pressure blocking patterns are weakening somewhat and slipping southward. As the meandering wobbles in our upper air flow give way to a more laminar flow, unsettled weather with high winds and heavy rainfall are anticipated to in parts of northern of England and Scotland. Yet again the cause is our jet, situated around 11km above the surface it is fiercely blowing along the western shores of Greenland, introducing a cool Arctic airflow downstream. As this air mass comes into contact with the mild and most south-westerlies in the north-east Atlantic it tends to activate instability and rapid cyclogenesis, the process involved in the development of our frontal weather systems. As a result, we expect a series of deep and compact low pressures to storm toward Scotland that may lead to flash floods and structural wind damage.

The cause of all this wacky and topsy-turvy weather patterns perhaps lies in the strength of the polar jet. As the temperature gradient between the subtropics and poles intensifies in a warming climate, we may expect to see an increase in “blocking patterns”, due to the formation of deep lows that spin-up and help maintain neighbouring high pressures.

Location of the NH jet streams during November. Red colours indicate where the upper level winds at 200hPa (11km) are blowing strongest. Adapted from the University of Wyoming GFS model run.

It is foreseeable that emergent patterns may arise in the behaviour of our jet as our climate warms, with long-term and predictable blocking features dominating the regional weather conditions over parts of the globe. One noticeable trend is that the European jet stream has been taking a two-way path of deflection, leading to interesting northerly bands in both weather patterns and temperature anomalies that deviate substantially from our typical climate. One upper air-stream has dived into North Africa and has traveled through the Mediterranean. Toward the North Pole, another jet stream has been observed crossing Scotland and Scandinavia, ending its extensive fetch in central Siberia. The key players in these “blocking weather patterns” are: emerging sea surface temperature anomalies through weakening of the over-turning meridional circulation(1), downward trends in the northern hemisphere ice coverage(2), expansion and poleward migration of the subtropical anticyclones(3), and rapid increases in the land-surface temperatures in contrast to the oceans(4). Low solar activity also plays a role in the meandering of the polar jet stream, with particular implications for extremes of winter cold over Europe(5).

Our growing concern is that science can be lost in the midst of secrecy, that’s why our energy demand calculator is now publicly available. The calculator provides vital information on the current temperature thresholds for several heating increments and is reported for 19 UK towns and cities. It can easily be adapted to predict your household heating bills. The heating degree day (HDD) data is based on the 1961 – 1990 averages that are reported as daily maximum and minimum temperatures. Furthermore, we have also released our jet stream blocking diversion model, which has been produced in the IDL computer programming language. Please stay in tune for our final winter weather prediction.

Further contact details …

e. forecasts@weatherlogistics.com ; m. 07949187732

References:

(1) Mignot, J., A. Ganopolski, A. Levermann, 2007: Atlantic Subsurface Temperatures: Response to a Shutdown of the Overturning Circulation and Consequences for Its Recovery. J. Climate, 20, 4884–4898

doi: http://dx.doi.org/10.1175/JCLI4280.1

(2) Climate Change 2007: Working Group I: The Physical Science Basis, FAQ 4.1 Is the Amount of Snow and Ice on the Earth Decreasing?

 http://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-4-1.html [Accessed November, 2011]

(3) Lu, J., G.A. Vecchi and T. Reichler, Expansion of the Hadley cell under global warming, Geophysical Research Letters , 34(6), L06805, 2007

DOI: 10.1029/2006GL028443

see also: Correction to “Expansion of the Hadley cell under global warming”, Geophysical Research Letters, 34(L14808), 2007, doi:10.1029/2007GL030931

http://www.agu.org/journals/gl/gl0714/2007GL030931/2007GL030931.pdf

(4) Sutton, R. T. Dong, B. Gregory, J. M., Geophysical Research Letters, Land/sea warming ratio in response to climate change: IPCC AR4 model results and comparison with observations, 2007, 34 (2), pages L02701

http://atmosdyn.yonsei.ac.kr/nrl/seminar/Sutton_etal_GRL2007.pdf

(5) Lockwood, M., Environmental Research Letter, 5(2), Are cold winters in Europe associated with low solar activity?, Environmental Research Letters, 2010

http://iopscience.iop.org/1748-9326/5/2/024001/fulltext

Confused? Well it may not be as daft as it sounds, as there are several strong links that tie together these two predictions – and its all down to the positioning of a stubborn high pressure system over the Atlantic Ocean …

At the moment a large high pressure system is sitting directly over Poland – and that is bringing many Europeans some welcomed sunshine and drawing hot southerly winds into England and Wales from Spain. The high pressure is not just a local affair, it is now extensive, spanning some 3000 miles to the Black Sea. We also know the high is characteristic of an omega blocking pattern, as the frontal systems that should be bringing us rainfall to our shores are straggling in a latitudinal direction. Rather than fronts crossing from West to Eastern Britain toward Norway, as they normally do, they are standing almost stationary around 15 degree due west. Furthermore, the jet stream which is responsible for directing the course of low pressures and their fronts is deflecting northward, transporting the cloud and damp weather over the top of Scotland and into the Norwegian sea.

So what does this mean for us ?.. One of the key features of a continental blocking high during the winter season is extremes of cold. This is especially the case in the UK and Ireland if the winds blow from an easterly direction. Whilst these conditions are not usually akin to Autumn, strong blocking patterns can make this plausible. The final autumn weather prediction produced by Weather Logistics UK  at the end of August indicated that extremes of cold weather were likely later in the season. This finding is supported by our unique jet stream – blocking interaction model, that used inputs of the strength (8.2/10.0) and the “preferred placement” (15°W) of semi-stationary high pressure patterns over the North Atlantic Ocean. The autumn and winter forecasts both show a strong blocking pattern and below average temperatures.

Blowin' Hot then Cold - October Weather of Extremes?

Seasonal temperature variability is strongly controlled by the transport of water vapour, water molecules in the gas phase. The passage of Atlantic air across Europe is extremely crucial to our water budget, bringing rainfall that irrigates our crops and gardens, but also in an invisible cloud of vapour that floats mysteriously above us. Water vapour provides a warm blanket that absorbs heat energy leaving the surface and reduces its transfer to space.  It is a potent greenhouse gas with surface mixing ratios typically more than a thousand higher than carbon dioxide accounting for up to 70% of our greenhouse effect. Unlike its counterparts such as carbon-dioxide and ozone, it is not a well-mixed gas, which means its mixing ratio in the atmosphere varies considerably both with height and spatially across the Earth’s surface. As a result, water vapour provides an irregular warming effect to our climate that tends to move in unison with our clouds. So weather systems that filter cloud into Europe also carry moisture over the continent, which exerts a regional warming on our climate.

Climate change itself can re-define the definition of typical seasonal weather…  Changeable patterns usually characterise the weather of the British Isles, providing a mix of sunshine and damp conditions. When weather patterns are disrupted or transformed by climate change, natural cycles or a combination of both, the normal seasonal weather patterns become misplaced. So regular inter-annual patterns of British snowfall in October is not only plausible, but it is a possible effect of climate change itself, if not paradoxically.

Location of blocking high during the autumn

A well positioned high pressure blocking, that sits over the European continent for a long period of time, continues to “cut-off” the input of water vapour into the atmosphere. Since high pressures are associated with subsidence and an outflow of air at the surface, conditions are exceptionally prone to dehydration. Dehydration is a general character of high pressure systems with net inflow aloft and inflow near the boundary later, as higher concentrations of water vapour are present in the lower portion of the atmosphere.

A second source of airflow dehydration is through large amplitude meandering of the upper level jet. This is a common feature of cold and dry winters in north-west Europe, when the polar jet stream is much weaker and further south than usual. The precipitation intensity downstream tends to be greater downstream of the blocking high, as weather systems are transported closer to the poles than usual. Whilst air experiences an intense cooling near the cloud base on the north-east limb of the blocking high that increases the rate of condensation and precipitation, further downstream a “shadowing” effect is experienced where conditions are generally much drier than average. As a result of this characteristic, an intense blocking high tends to increase the variability in seasonal weather conditions and also enhances the likelihood of extremes in drought, heat waves and flooding.

Although the global mean average in relative humidity does not show a strong seasonal pattern, absolute humidity is coupled to annual cycle in daily temperatures, with reductions (enhancement) in its total column concentration tending to lower (increase) the average temperature in a cloud-less atmosphere. An interesting feature is that the link is two-way, with temperature and water vapour both playing the role in process of cause and effect. Water vapour can either be explained by its role as a forcing or feedback in the climate system. As a positive feedback through natural variability in cloud-cover and the hydrological cycle, it leads to rises and falls in the short (hours to days), medium (up to several weeks) and long-range (seasonal to decadal) temperature signal as a potent greenhouse gas.

Cold air tends to stick around for a long time … As cold air collects over the European continent, its relatively higher density in comparison to warmer and moister air resists the surface air-flow that attempts to dislodge it. Cold and dry air in the boundary layer is extremely hard to shift, so the longer a high pressure “sits put” over Europe during the autumn to winter periods the more likely it is to stay.

So with a blocking high dominating the scene of the British Isles, it is likely that the weather may take a cold turn by the end of October …

Our seasonal forecasts includes graphs and a more detailed outlook … <Click here to Purchase>

Does seasonal weather affect your business?

How does climate change impact upon seasonal predictions?

For further details, please contact the Project Manager @ Weather Logistics UK

e. forecasts@weatherlogistics.com

m. 07949187732

*Comments and feedback are welcomed. Would you like to know more about the weather forecast product for 2011? Are you unsure about any of the information presented in this article? Can you suggest any improvements?

Seasonal Forecast for Autumn 2011 (Shortened)

Our full report includes graphs and regional forecasts … Click to Purchase

Valid from: 1st September until 30th November 2011

Issued: 30th August, 2011 (Final Edition)

Blocking Index: 8.2/10.0 (upper third on scale)

Strong preference toward negative phase of the North-Atlantic Oscillation: Prominent blocking high, which is more likely to be proximal to the UK. A cool and dry theme is now likely to dominate during the autumn period. Some major blocking patterns close to the British Isles may give rise to warm conditions in the south of England during September, whilst some severe cold and frosty periods are likely later in the season.

General Overview:

During the autumn 2011 season, temperatures are expected to close to average or well below for much of the United Kingdom and Republic of Ireland with an anomaly of -0.7 ± 0.4°C (-1.3 ± 0.7°F). Much of this cool anomaly is due to well below average sea surface temperatures in the North Atlantic Ocean. The effects of climate change act to counteract this anomaly, with a global trend of close to +1.0°C (1.8°F). As a result, the energy required for heating a household or work-place is likely to be around average at 11 ± 7% – a significant increment above the 1961 – 1990 average. Since surface temperatures have slowly been increasing over the British Isles, this represents a cool autumn (typically a 1 in 10 year event). Snowfall is generally rare during the autumn period; and the SnowCast predictions undertaken by Weather Logistics UK indicate well above average snow day events across much the UK and Ireland, with snow-day events typically 15% more frequent than usual.

The early autumn weather will be on the wet side of average over Northern Ireland, Scotland and Northern England as the September jet stream lies much further north. As such, rainfall totals are likely to be around -11 ± 25% below the norm (with rainy days -7% below average) with the driest weather in the latter half of the autumn period. The North Atlantic Oscillation (NAO) is also expected to be more positive (less strongly negative) early in the season, again indicating some stormy conditions during September. Later in the season, a gradual shift to La Nina conditions in the Pacific Ocean will tend to give rise to much cooler conditions, as high pressure and a continental weather pattern begins to dominate the scene. Our jet-stream predictions indicate that wetter weather is more likely in South-west England, Wales and North-West England, where frontal systems will pass frequently. High pressure and dry weather conditions further south may at times lead to some warmer days from September to mid-October particularly for the southern counties of England.

In summary: A dry and cool autumn than average for many parts of the UK and the Republic of Ireland. The weather is likely to start unsettled over much of Northern England and Scotland, whilst turning wet in the southern and western counties later. There is an increasing risk of Arctic winds or easterly winds during late October into the end of November as the long term weather swings from near-neutral NAO indices to strongly negative values later in the season. The Republic of Ireland, Wales, South-west and Central England are more likely to experience changeable weather for much of the autumn period, in contrast to the North and Eastern counties.

Updates from last month …

Our NAO forecast has been reduced from last month to an index value of -0.5, so we anticipate that high pressure conditions are more likely over the North Atlantic Ocean close the British Isles for much of the autumn period. We have also increased the blocking index to 7.3 from 8.2, which indicates drier conditions than in our July forecast. Our empirical adjustment is strongly influenced by unseasonably cool sea surface temperatures in the North Atlantic Ocean, demonstrating that a long-term blocking pattern is beginning to introduce a much cooler airflow into the British Isles. As a result, the autumn temperatures are expected to a further 1.0°C cooler than our previous forecast with Arctic air flows more likely. The energy required for household or business heating is now 33% greater than our forecast issued at the end of July, in the well-average category of 633 to 672 heating degree day units. The increased blocking pattern has acted to shift the rainfall patterns from north to south, with wetter conditions now more likely around the south-west of England and Wales.

Our full report includes graphs and regional forecasts … Click to Purchase

Our first monthly edition of our winter weather prediction is also available for subscription for businesses. Does seasonal weather affect your business?

How does climate change impact upon seasonal predictions?

For further details, please contact the Project Manager @ Weather Logistics UK

e. forecasts@weatherlogistics.com

m. 07949187732

*Comments and feedback are welcomed. Would you like to know more about the weather forecast product for 2011? Are you unsure about any of the information presented in this article? Can you suggest any improvements?

Weather Logistics UK anticipates that the remnants of Katia will reach the UK from Monday morning onward. It will be combined with wave heights of up to 12 metres and storm surges on the north and west coasts, particularly on the south-east quadrant of the system. Throughout Scotland and Northern Ireland severe gales may also cause widespread structural damage to buildings, with estimated risks of 20 to 30% that sustained winds will reach storm-force and with gale force winds or stronger very likely.

An intense tropical storm in the Atlantic basin is called a hurricane, often possessing an “eye” of clear-sky that can be viewed from space-borne instruments. The tight isobars that pack around these storms are characterised by sustained wind speeds above 76 mph. Hurricanes are a prominent feature of the north-west Atlantic basin and Gulf of Mexico, where tropical disturbances gather latent heat energy from clusters of thunderstorms that infrequently make land-fall in the USA during the early summer to late autumn season. Initially forming as localised depressions, these cloud masses move northward into the sub-tropics where they can spin-up into deep low pressure systems. They are often steered in a north-westerly direction by the sub-tropical jet stream where they are fed by moisture over warm sea surface temperatures, developing in their viciousness and in their girth, with compact radial pressure gradients. In addition, spiralled bands of thundery rain develop around these tropical storm disturbances, twirling outward from the central low pressure. The resulting weather conditions consist of tornadoes and convective instability, causing gusty winds combined with thunderstorms and heavy blustery showers.

Our final seasonal weather prediction for autumn 2011 is currently on Amazon Kindle and by subscription (using the links on the right of this page). Although we expect stormy and wet weather for the British Isles during September, we anticipate that the general weather pattern will settle down dramatically during the latter part of the season with high pressure dominating from late September onward. Early signs from the global forecasting system (GFS) indicate that sunny but cool conditions will begin to set in by mid-September, with the jet stream slipping southward blocking the passage of Atlantic storm systems. From the mid-autumn period onward Weather Logistics UK predicts that hurricanes, and the remnants they leave as extra-tropical storms, will dissipate over the USA as they begin to track further southward.

Our first monthly edition of our winter weather prediction is also available for subscription for businesses. Does seasonal weather affect your business?

How does climate change impact upon seasonal predictions?

For further details, please contact the Project Manager @ Weather Logistics UK

e. forecasts@weatherlogistics.com

m. 07949187732

*Comments and feedback are welcomed. Would you like to know more about the weather forecast product for 2011? Are you unsure about any of the information presented in this article? Can you suggest any improvements?

Leisure Activities…Transport Networks…Estimating Gas and Heating Oil…Estimating Summer Air Conditioning Bills…Planning for Events…British Tourism…Insurance Firms…Energy Companies 

How do they work?

(1) High pressure blocking patterns over the North Atlantic Ocean are associated with cold and dry weather conditions in Britain during the winter season *[(a), (b), (c)] …

… The upper atmospheric model constructed at Weather Logistics UK simulates the flow diversion from semi-stationary upper level features. Using upper air data, we perform calculations to produce a set of proxy data that describes the position of monthly jet streams and how their trajectory is likely to be altered by transient eddies of varied intensity. Although these blocking highs do not reside over a fixed region indefinitely, we can predict their “preferred” locations using numerical weather prediction outputs. We then use the NAO index to predict how often we may expect to experience the effects of blocking at a given region. For example a blocking pattern is expected to occur much more often when the NAO is strongly negative, typically more than 2 in every 3 days during the winter season. Furthermore, the model explores permutations of different blocking patterns, allowing us to express the likelihood of their occurrence at different locations and of different intensities.

Our model demonstrates proof of concept that strong blocking patterns in the vicinity of the British Isles induce a cool-dry seasonal signal. This effect diminishes as model input of the blocking index is lowered. The signal is much more pronounced in the measurement data during the winter season, when our seasonal weather predictions perform with much more success.

The Science of the Problem?

Over the Northern Hemisphere extra-tropics, the prevailing air flow direction is westerly in the upper atmosphere.  An Atlantic blocking feature within close proximity to the British Isles can have a dramatic impact on the prevailing weather conditions, depending on several variables. Firstly, a blocking pattern in the Atlantic Ocean deflects the upper air stream into an omega shaped pattern, diverting the air stream farther northward and then southward as it gains extra “spin”. It is the extent of the northward fetch that acts to cool the observed seasonal temperatures, as low pressure systems tend to travel over lower sea surface temperatures before veering toward Britain. This blocking – jet interaction both reduces the frequency of passing storm systems and exposes the UK and Ireland to much cooler polar air. In contrast, when blocking is weak or the upper air flow blows more westerly, Britain tend to experience much higher winter temperatures.

The other variables that affect the British weather are the latitude of the jet, the strength of the N-S gradient in sea surface temperatures, the phase of the North Atlantic Oscillation (NAO) and the position of the “blocking high”. The flow interaction is most dominant when high pressures tend to occur more frequently around 15 degrees westward of the British Isles. Blocking is also more influential when the jet-stream position is less variable in the mid-Atlantic, just south of Greenland and is located at the same latitude of Central England. Climatological data predicts that the jet stream latitude meets these criteria best during the winter months, and this is also when sea temperatures are much colder over the Arctic than the Azores producing a strong signal of cold weather blocking. The negative phase of the NAO also becomes more pronounced during the winter months, enhancing the cold signal from any proximal blocking pattern observed in the north east Atlantic Ocean.

(2)  The Clausius-Clapeyron relation describes the maximum amount of water that can be held as vapour at a given temperature and pressure. It has a direct influence on our predictions of seasonal rainfall totals, amplifying any drying or moistening influence of blocking features over the North Atlantic Ocean  …

… over-saturation of air in the presence of microscopic particles called cloud nuclei results in condensation and the formation of liquid cloud droplets. When the number density of water molecules in the atmosphere exceeds a critical value, the collisional energy increases at a greater rate than the kinetic energy, so a further input of heat or decrease of pressure is required to retain more water molecules as vapour. The Clausius-Clapeyron relationship is a derivation of the law of thermodynamics, a set of equations that describe how heat energy is transferred between solids, liquids and gases. Water vapour, ice and liquid water are in constant transition within the Earth’s atmosphere and are in a state of 3-d motion. As a result, there is a constant transfer of energy between molecular, kinetic, gravitional potential and thermal sources.

Our model considers this problem by calculating the relative difference in what is known as the “saturation vapour pressure” between the 1961 – 1990 temperature climatology and our predictions of temperature for a given region during the same season.

Flooding due to sporadic rainfall events (thundery showers) are now much more frequent and extremes of wet and dry weather are now more common – an impact that can either be dampened or amplified on a regional scale by a strong blocking pattern in the upper atmosphere. Evidence from the DEFRA UK Climate Projection Centre predicts a steady trend toward wetter summers in the north and hotter and drier summer in the south of the British Isles due to a gradual northward shift of the polar jet stream as the world warms. For further information please contact us below, or view our information about climate and seasonal prediction.

The Science of the Problem?

Evidence from global observations indicates that extremes of floods and droughts are becoming more frequent *[d, e, f, g]. This is a direct effect of warmer temperatures on the perturbation of the hydrological cycle. What we tend to observe in a warmer climate, or during warm-than-average season, is an enhanced precipitation intensity from an overall rise in the absolute humidity (or amount) of water that the atmosphere is able to hold. Whilst the number of rainfall events is dominated by the odds of an air stream transporting clouds and storm systems toward our shores, the rainfall intensity during a given “rainy-day” event is intrinsically linked to the average seasonal temperature.

Does seasonal weather affect your business? How does climate change impact upon seasonal predictions?

For further details, please contact the Project Manager @ Weather Logistics UK

e. forecasts@weatherlogistics.com

m. 07949187732

*Comments and feedback are welcomed. Would you like to know more about the weather forecast product for 2011? Are you unsure about any of the information presented in this article? Can you suggest any improvements?

*References …

(a) Sillmann et al., 2011, doi: 10.1175/2011JCLI4075.1,“Extreme Cold Winter Temperatures in Europe under the influence of North Atlantic Atmospheric Blocking”, Journal of Climate

(b) Mark Kinver, April 2010, Science and environment reporter, “Low solar activity link to cold UK winters“, BBC News (online)

(c) M Lockwood, June 2010, Volume 5 number 2,“Are cold winters in Europe associated with low solar activity?”, Environmental Research Letters

(d) Seung-Ki Min et al., 470, 378–381,“Human contribution to more-intense precipitation extremes”, Nature (Letters)

(e) Pardeep Pall et al., 470, 382–385, “Anthropogenic greenhouse gas contribution to flood risk in England and Wales in autumn 2000″, Nature (Letters)

(f) Richard P. Allan, 470, 344-345, “Climate change: Human influence on rainfall”, Nature (News and Views)

(g) George Monbiot’s Blog, Feb 2011, “Climate change and extreme flooding linked by evidence”, The Guardian

In fact, for this reason, the techniques used to describe seasonal weather predictions show great similarities to climate change predictions. Both make use probabilities to estimate the likelihood of different weather events over longer time frames. The key difference that sets climate and seasonal predictions aside, is a natural cyclical process known as inter-annual variability that is almost entirely absent in climate change predictions. Numerous irregular fluctuations in the regional and global weather patterns result from the uneven heating of the Earth from the Sun, chaotic cloud and ice responses to seasonal temperatures and ocean circulation patterns. All of these components of the climate system operate over a large spectrum of time and space scales. In the Meteorological community, the term climate refers to the average weather patterns that associated with a specified region, which acts to smooth over the irregular wiggles in the weather data.

Although climate change is talked about a lot by the media and the scientists, many of us struggle to comprehend exactly what it means and how it may affect our lifestyle in the future. This is where seasonal weather predictions can add some clarity and confidence to the world of scientific prediction. Whilst few of us will recall the changes in our climate over decadal scale time frames, many of us will remember summers of extreme heat and the complete wash-out of 2009. Indeed, it is clear that climate averages alone do not bode well with businesses and individuals that depend on long term weather patterns. This is because seasonal weather patterns vary considerably from one year to the next. In contrast, climate averages are formed by averaging over at least 30 years – or much longer.

Seasonal weather predictions can give an insight into the likelihood of different weather events, increasing our awareness of regions that are at risk of a specified weather type during the next few months. With a largely undiscovered market potential, many factors such as the frequency of heavy showers, regional temperature anomalies or wind patterns can make a big difference to how businesses operate. It is this foresight that adds value to the insurance, retail, leisure, transport, energy and agricultural sectors.

Does seasonal weather affect your business?

How does climate change impact upon seasonal predictions?

For further details, please contact the Project Manager @ Weather Logistics UK

e. forecasts@weatherlogistics.com

m. 07949187732

*Comments and feedback are welcomed. Would you like to know more about the weather forecast product for 2011? Are you unsure about any of the information presented in this article? Can you suggest any improvements?

The ninth storm of the Atlantic hurricane season, which will be responsible for next weeks bad weather, is presently known as Hurricane Irene. The named storm is currently a deep area of low pressure, with a central pressure of 942mb reported on Thursday at 8pm EDT. Irene is currently positioned some 600 miles north of the Bahamas, and its shear size is fearful. The Atlantic storm occupies some 0.8 million square miles (4m sq km), 0.8% of the Earth’s surface – much bigger than many other tropical storms in history and with a large potential for high economic damage as its projected path extends along the entire eastern US coastline. But the trouble from Irene does not remain in America. Medium range forecasts indicate that the trouble from Irene will not be over when it leaves the eastern coasts of the USA.

As the cyclone returns to a extra-tropical storm status it is expected to swing westward, reaching the British Isles by the early part of September. The storm will pose a hazard for transport networks, homes and industry prone to flooding and some infrastructure in parts of Scotland such as the Western Isles and Shetlands.

The extra-tropical storm is due to produce heavy rain and strong to gale force winds for much of northwest England, Northern Ireland and Scotland. Meanwhile, blustery showers are expected for more southern counties of the UK, with temperatures taking a tumble to mid-autumnal values.

Hurricane Irene recently became a Category 2 hurricane Monday evening with maximum sustained winds in excess of 100 mph close to its centre. Although these winds are sufficiently strong to cause extensive damage to infrastructure and cause storm surges in parts of the US, this is not the largest danger posed by the storm. Its monstrous 700 mile diameter consists of many broad spiralled rain-bands, associated with heavy thundery rain, squall lines, gusty winds and tornadoes causing havoc in its wake.

For details about our seasonal weather predictions for the UK and Ireland please contact:
e. forecasts@weatherlogistics.com
m. +447949187732

Seasonal weather forecasts for the United Kingdom and Ireland

*Comments and feedback are welcomed. Have you been directly affected by Hurricane Irene, or are you preparing for the tropical storm in the USA? Are you unsure about any of the information presented in this article?