Orbit: Episode Three

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    Aira Idris Aira Idris | 21:45 PM, Sunday, 18 March 2012

    In our journey so far we have explored the impacts of the Earth's Spin and Orbit on the weather and climate.

    The final instalment of the series explores the influence of the tilt on the Earth's weather and climate, and how the Earth's relationship with the Sun affects the way we live our lives.

    Originally the series was called 23 Degrees, (the angle of the tilt) as we considered this factor extremely significant to the variability in seasons our planet experiences. Although the series is now called Orbit, the tilt of the Earth continued to be an extremely important factor of the series. What do you think?

    From the arrival of spring in the Hay river to the affects of the monsoon to the people in India, we wanted to uncover how Nature and culture respond to the variations in the Sun's energy.

    Kate takes us through the ancient archeological site Chichen Itza, Yacatan region of Mexico. At its peak, in the 10th century AD it was a thriving city that sprawled over 25 square kilometres and was home to more than 40000 people.

    We wanted to explore how ancient civilizations had developed a great understanding of our Earth's journey around the Sun, and Kate takes us there on a significant day; the March Equinox. How significant are sites such as temple of Kukulkan and Stonehenge to us today?

    In this episode we also wanted to breakdown the key factors that drive the extremes of weather like the Monsoon, Dust storm and the Tornado.

    Helen travels to Kerala, South of India to discover what drives the Monsoon and visits Tornado Alley with atmospheric Scientist Josh Wurman to explain 'What causes a tornado?'

    A record six EF-5 tornadoes were confirmed in 2011, the most deadly being Joplin Missouri tornado (158 killed, 14 mile path length.)

    What do you think about Episode three? How significant do you think the Earth's tilt is to our climate and weather? How far are we in understanding why one supercell drops a tornado and another doesn't? Has our cultural relationship with the Sun changed over time? Leave your comments on this post.

    System in Atlantic rapidly develops - Scotland braced for 90mph gusts

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    Dave Britton – Met Office | 15:30 PM, Wednesday, 7 December 2011

    Distance travelled ~ 876'413'600 km

    The depression is expected to bring gales and heavy rain from the west for Thursday.

    uk severe weather warnings


    Snow is likely for a time on Thursday morning across parts of central and northern Scotland, particularly affecting higher ground, but with some slushy deposits locally to lower levels, and all parts of the UK will have heavy rain for a time during the day.


    But the main feature of this depression is the gale to storm force winds it will bring. Gusts of 60 to 70 mph likely to become quite widespread across northern and central Britain, but 70 to 80 mph are expected across much of Scotland with 90mph gusts are possible in exposed places, particularly central and southern Scotland. Elsewhere across England and Wales the wind will gusts of 50-60 mph. (Warnings issued by the Met Office)


    latest europe satellite image



    As the storm passes through and moves away to the east of the UK on Friday north-westerly winds will bring in cold air which will see a drop in temperatures. This is expected to bring snow to northern and western parts of the UK, giving accumulations to low levels in the north. Accumulations will tend to be confined to higher ground across north Wales and much of northwest England. Untreated surfaces will also become icy at times. Other parts of the country will see a cold night on Friday with widespread frost.


    The forecast for the rest of the month is for the unsettled weather to continue, with spells of wet and windy weather interspersed with brighter, colder periods when we can expect to see frost and snow showers - the heaviest of any snowfalls are expected across higher ground from North Wales northwards, but we could occasionally see some snow cover at lower levels as well.

    Day 332 Severe weather watch: deep depressions

    Distance travelled ~ 853'365'600 km

    UK and World weather report:

    The UK's recent quiet weather took a dramatic turn last week as fog gave way to gales and heavy rain. The foggy start to the week, with visibility down to below 50m in places in the south and east on Monday and Tuesday.

    Despite a colder night on Tuesday, with a minimum of - 2.3 °C and widespread ground frost across England and Wales, temperatures remained a little above normal throughout the week, with a high of 15.9 °C at Fyvie Castle in Aberdeenshire on Saturday.

    On Thursday, a rapidly deepening area of low pressure moved past the north west of the UK, bringing severe gales over the far north west as well as persistent and increasingly heavy rain that continued into Friday and over the weekend.

    storm force winds thurso, scotland

    Storm force winds hit Scotland over the weekend. Image captured by Debbie Bozkurt Sunday 27 November

    Cassley in Sutherland recorded 66.6mm of rain in 12 hours, gales affected northern Scotland, peaking with a gust of 90mph at Fair Isle on Sunday morning. The storms left about 400 homes without power in Orkney, caused landslides, and A cargo ship sunk after reportedly being rolled over by a wave and breaking in two in the Irish Sea.

    Elsewhere in the world, heavy rain is continuing to cause problems. In the Philippines, six people were killed in flash floods after continuous rains in the area caused local rivers to overflow. In Australia, floods have left thousands cut off in the town of Wee Waa in New South Wales. The town will only be accessible by boat and helicopter for at least a week.

    Meanwhile, Mexico is suffering its worst drought in 70 years. Due to the lack of rainfall the government has forced been to supply water to nearly 2.5 million people across eight states.

    The week ahead


    • A very unsettled week for the whole country, with several deep depressions moving in off the Atlantic.

    uk infrared satellite image


    Latest infrared satellite image of British Isles

    uk forecast rainfall


    • Periods of heavy rain, especially in the west of Scotland, could cause some flooding problems. Also windy at times, with a continued risk of gales. There is risk of snow over the higher ground of northern Britain at times.


    Across the North America:

    • A deep depression is moving eastward across Canada, bringing strong winds and snow to many areas.

    satellite image canada

    GOES-EAST/WEST infrared satellite image 14:45 UTC. Data courtesy of NOAA.

    By Tuesday, it is expected to lie over the Hudson Bay, with particularly windy conditions on its southern flank possibly affecting coastal Ontario, Manitoba and Quebec.

    • Another depression, moving northwards towards the Great Lakes from the Gulf of Mexico over the next few days, will also bring heavy rain to places in between as it passes.

    Across Africa:

    • Cooler than average conditions extending from Saudi Arabia across Sudan, Chad and perhaps even reaching northern Nigeria. Conversely, warmer than average across much of Madagascar.

    Across Asia:

    • A spell of wet weather is expected for Saudi Arabia, Kuwait, Bahrain, Qatar and the northern Gulf on Monday and Tuesday. Rainfall totals of 40-60 mm are likely, with flash flooding a possibility. This is the first significant rainfall since the spring in this area. It is also unseasonably cold, both in this region and more widely across the Middle East.

    • Some rather windy conditions likely for Oman, especially coastal regions and particularly later in the week, in association with a deep depression. This is also likely to impact on coastal parts of Karnataka, Kerala and Goa in India for the next day or two.

    Across Australasia:

    • Some large temperature variations across southern Australia this week, with south western parts going from cool to warm and south eastern areas swinging from warm to cool.

    • Heavy rainfall is set to continue in Australia and Asia due to a La Nina pattern in the Pacific Ocean.

    Saturn's super-storms quite unearthly...

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    Mark Thompson Astronomy Mark Thompson Astronomy | 18:00 PM, Friday, 11 November 2011

    Distance travelled ~ 809'788'800 km

    High winds are a common occurrence on Earth but they don't often reach more than 150km/h. The record is held by the Tropical Cyclone Olivia as it moved across Australia in April 1996 which battered the land with gusts of 408 km/h. This is nothing compared to the rather more serene and beautiful looking planet Saturn. High in the atmosphere of this gas giant the wind speeds have been measured at a staggering 1800km/h.

    The concept of what causes wind, which is effectively the flow of gas from one place to another, is pretty simple to understand. Take the Earth for example; warmth from the Sun heats the surface which then in turn heats the atmosphere in contact with it. As the air warms, it becomes less dense than the surrounding air causing it to rise which results in an area of low pressure as 'less air' is present. Other surface air will then rush in to effectively fill the void left from the rising air and we experience that as wind.

    The storms we see on Earth are just extreme versions of this with areas of particularly low pressure at the centre. Typically they form over the oceans which are a vast reserve of energy. Water is very good at storing and retaining incoming solar energy and its this along with the moisture that gives storms their awesome power.

    On Saturn the extreme storms that drive the winds are very similar in structure to those on Earth with low pressure systems but it's the source of the energy which sets them apart. Instead of vast bodies of water, the heat driving the storms on Saturn comes from deep within the planets core. When it formed around 5 billion years ago heat was generated when the pieces from the proto-planetary disk crashed together and its the slow but steady release of this energy which has driven Saturn's super-storms.

    NASA's Cassini spacecraft captures a view of storm churning through the atmosphere in Saturn's northern hemisphere

    Image credit NASA

    The Cassini spacecraft witnessed first hand one of Saturn's ferocious storms whilst it was orbiting the planet in December 2010. It was quite lucky given that Saturn is usually relatively storm free, unlike Jupiter however the lucky break gave planetary scientists a unique insight into the local weather system. The images show the storm covering nearly 4 billion square km and analysis of the lightning strikes showed a ten times more flashes than in other storms studied since 2004.

    UK and World weather report: unseasonable snowstorms & monster icebergs

    Distance travelled ~ 799'068'800 km

    October was a mild month - with some exceptionally high minimum temperatures for the time of year - ending with another mild day on Monday. Several locations did not dip below 15 °C all day and a top temperature of 19.3 °C was recorded at Kinloss. As the week continued into November, the mild temperatures carried on, with a high of 18 °C at Heathrow and St James' Park on Thursday.

    Rain dominated the week, with occasional rain on Monday turning into a band of heavy rain on Tuesday and widespread heavy and sometimes thundery outbreaks on Wednesday and Thursday. There were also some possible funnel cloud sightings, one of which may have touched down in Astwood Bank, just south of Redditch.

    Friday bought more wet weather, with intense rain in parts. Alice Holt Lodge near Odiham, Hampshire, recorded well over 50mm of rain between midnight and 7am, and there were numerous reports of localised flooding in the Home Counties.

    The weekend was slightly cooler, with a chilly start to both days and frost in many northern areas on Sunday morning.

    Elsewhere in the world, flooding continues in Thailand. A third of the country has now been affected by flooding after three months of heavy rain. Over 500 people are said to have died and there are fears that the flooding could worsen in the capital Bangkok.

    Thailand Floods October 2011

    Image Credit Remko Tanis

    Deadly flash floods also hit the Liguria region of Italy on Friday after heavy rain. Two rivers in Genoa reportedly broke their banks as floodwaters poured through the port city for the second time in eight days, killing six people. Much of northern Italy was affected by the heavy rain during the day, including Venice, which also suffered flooding.

    Close to two million homes are still without power after an unseasonable snowstorm hit the US east coast last weekend. The storm, which brought up to 76 cm of snow in parts, has been blamed for as many as 19 deaths. At the storm's height, three million homes were without power, while states of emergency were declared in New Jersey, Connecticut, Massachusetts and parts of New York.

    Scientists are monitoring the birth of a monster iceberg in west Antarctica. The iceberg is expected to break away towards the end of the year or early in 2012. Currently, the crack is 30 kilometres wide and 60 metres deep and growing every day. Researchers from NASA expect the eventual iceberg to cover 880 square kilometres - an area the size of Berlin.

    Operation Ice Bridge

    Image Credit NASA

    Path of Ice bridge

    Image credit NASA

    The week ahead

    In the UK:

    • Monday and Tuesday will be dull and cloudy and occasionally damp across the country, but temperatures will be mild. Wednesday and Thursday see more persistent rain moving into western areas, while the east may become a little brighter. Staying mild, especially overnight, with light southerly winds. As we head into the weekend mild southerly winds should bring broken cloud to many parts.

    Elsewhere in the world:

    • There is the potential for a tropical cyclone to form in the Arabian Sea. A depression was centred about 700km east-southeast of Salalah on Monday and the system is forecast to intensify further into a deep depression and move towards the Oman coast over the next three days.

    • A tropical depression formed close to Hainan Island in the South China Sea on Monday. China mainland provinces of Guangdong and Fujian, the island province of Hainan, as well as Taiwan, will be subject to the periods of heavy rain through much of the week.

    • Unsettled periods of weather look set to affect the western Mediterranean, parts of Canada and northern Russia, although nothing particularly exceptional is currently signalled.

    • Over the USA, an outbreak of potentially damaging thunderstorms and tornadoes looms for the southern Plains on Monday. The thunderstorms may ease for a time overnight and into Tuesday, but is forecast to increase once again on Tuesday afternoon with the threat zone stretching from central Missouri to East Texas and Louisiana.

    • Unseasonably cold conditions are forecast across the Caucasus', spreading to much of the Middle East through the week.

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