Monitoring and forecasting the UK climate and its meteorological changes with analysis

UK Climate Forecasting and Analysis

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The images Courtesy of NOAA Star show the satellite image of the US Atlantic Coast and the Lower Level Water Vapour on Wednesday 2 April at 15.16 hours

Due to the rotation of our planet and the Coriolis effect in the Northern Hemisphere winds are blown to the right across the North Atlantic to Ireland the UK and Scandinavia so we have to look at the weather in North America and the direction of the Polar Front Jet Stream. The Coriolis effect increases in strength the nearer you get to the poles and is responsible for large cyclones or depressions. The weather in the North Atlantic is influenced by the 23.4° tilt in the axis of the Earth as the seasons are caused by variations in the angle of the sunlight hitting the Earth and are one of the major causes of Atlantic storms. We will research these meteorological changes and analyse data which effect the UK.

Why is lower-level water vapour band imagery important? The 7.3 µm “Lower-level water vapour” band is one of three water vapour bands on the ABI. It typically senses farthest down into the mid-troposphere in cloud-free regions, to around 500-750 hPa. It is used to track lower tropospheric winds, identify jet streaks, monitor severe weather potential, estimate lower-level moisture (for legacy vertical moisture profiles), identify regions where the potential for turbulence exists, highlight volcanic plumes that are rich in sulphur dioxide and track Lake effect snow bands.

The Atlantic Ocean is the second-largest of the world's oceans. With a total area of about 41,100,000 sq miles it covers approximately 20% of the Earth's surface and about 26% of its water surface area. The average depth of the Atlantic with its adjacent seas is 3,339 metres or 10,950 ft without them it is 3,926 metres or 12,880 ft. The greatest depth is the Milwaukee Deep at 27,500 ft in the Puerto Rico Trench. The Atlantic's width varies from 1,538 nautical miles between Brazil and Sierra Leone to over 3,450 nautical miles in the south. The principal feature of the bottom topography is a submarine mountain range called the Mid-Atlantic Ridge which is moving at 2.5 cm per year. It extends from Iceland in the north to approximately 58° South latitude reaching a maximum width of about 860 nautical miles. The Mid-Atlantic Ridge separates the Atlantic Ocean into two large troughs with depths from 12,000–18,000 ft. Transverse ridges running between the continents and the Mid-Atlantic Ridge divide the ocean floor into numerous basins. Some of the larger basins are the Blake, Guiana, North American, Cape Verde and Canaries basins in the North Atlantic. A great rift valley also extends along the ridge over most of its length. The depth of water at the apex of the ridge is less than 8,900 ft in most places while the bottom of the ridge is three times as deep. The Atlantic Ocean is a major source of atmospheric moisture through evaporation and traps around 30% of the carbon dioxide emitted into the atmosphere by human activity. The waters circulate in a clockwise direction. The Gulf Stream carries more water than all the world’s rivers combined and has it moves north its salinity increases. The Sargasso Sea has above average salinity.

UK Climate Forecast  38 Union Street  Grantham  Lincolnshire NG31 6NZ   

Oceanic currents are driven

 by three main factors

1. The rise and fall of the tides. Tides create a current in the oceans which are strongest near the shore and in bays and estuaries along the coast. These are called "tidal currents." Tidal currents change in a very regular pattern and can be predicted for future dates. In some locations strong tidal currents can travel at speeds of 8 knots or more.

2. Wind. Winds drive currents that are at or near the ocean's surface. Near coastal areas winds tend to drive currents on a localised scale and can result in phenomena like coastal swells. On a more global scale in the open ocean winds drive currents that circulate water for thousands of miles throughout the oceans.

3. Thermohaline circulation. This is a process driven by density differences in water due to temperature and salinity variations in different parts of the ocean. Currents driven by thermohaline circulation occur at deep and shallow ocean levels and move much slower than tidal or surface currents. Currents affect the Earth's climate by driving warm water from the Equator and cold water from the poles around the Earth.

The Florida current can be considered the "official" beginning of the Gulf Stream System. It is defined as that section of the system which stretches from the Florida Straits up to Cape Hatteras. It is a key component of AMOC with low salinity. The current was discovered by Spanish explorer Juan Ponce de León in 1513. The Florida Current receives its water from two main sources, the Loop Current and the Antilles Current. The Loop current is the most significant and can be considered the upstream extension of the Gulf Stream. The Gulf Stream together with its northern extension the North Atlantic Drift is a warm and swift Atlantic ocean current that originates in the Gulf of Mexico and stretches to the tip of Florida and follows the eastern coastlines of USA up to Newfoundland before crossing the Atlantic Ocean to Ireland UK and Western Europe making the region about 5 C warmer.

 

At 17.26 hours on Friday 28 March a large 6.6 magnitude earthquake hit the central Mid-Atlantic Ridge at a depth of 6.4 kilometres. At 14.24 hours on Wednesday 2 April a 5.2 magnitude earthquake hit the central Mid-Atlantic Ridge at a depth of 10 kilometres. In the North Atlantic the ridge separates the North American from the Eurasian plate and the African plate north and south of the Azores triple junction.

Mid Atlantic Waters on Wednesday 2 April: A nearly stationary front over the S waters will begin to lift N later this morning through tonight then is expected to move N of the area on Thu night. A low pressure trough crossing the N waters early this morning will pass E of the area today. High pressure will build SE over the N waters today, then shift E and NE of the area tonight while a ridge extends W and SW across the the southern waters through early Fri. A cold front will move S into the N waters late Thu night and Fri, then stall over the central and northern waters Fri into early Fri night, before lifting back N as a warm front later Fri night through Sat night. Yet another cold front will approach the area from the W Sun and approach the coast Sun night.

North Atlantic on Wednesday 2 April: The Atlantic basin is dominated by 1032 Mb high pressure centred near 34N45W, with the subtropical ridge axis extending westward toward central Florida. A complex low northeast of the Azores is supporting strong N winds and rough seas north of 24N and east of 40W. Elsewhere, this pattern is supporting fresh trade winds and 8 to 10 ft seas across the tropical Atlantic south of 24N, and gentle to moderate breezes and 5 to 7 ft seas north of 24N and west of 40W. For the forecast west of 55W, high pressure will persist across the area. The building high will support fresh to strong E to SE winds and rough seas across the waters south of 25N, including through the Atlantic Passages into the Caribbean.

Monsoon Trough: The monsoon trough axis enters the Atlantic Ocean near 12N15W to 02N20W. The ITCZ extends from 02N20W to 02S30W to offshore of northern Brazil near 02S45W. Scattered moderate convection is noted from 01N to 03N between 05W and 25W.

Caribbean Sea: For the forecast, fresh to strong winds and rough seas offshore of Colombia and in the Gulf of Venezuela will increase to near-gale force Wed through the weekend. Rough to very rough seas are expected with these winds. Fresh to strong E to SE winds in the Gulf of Honduras will increase to near-gale force speeds, with rough seas developing for the second half of the week. Elsewhere, moderate to fresh trade winds will strengthen with building rough seas dominating the basin Thu into the upcoming weekend. Large E swell will impact the tropical Atlantic waters and Caribbean Passages most of the week, maintaining rough seas.

Gulf of America: For the forecast, fresh to strong SE to S winds will persist across much of the basin west of 85W tonight. These winds will support building rough seas in this region the middle of the week through late week. East of 85W, moderate SE winds will strengthen to fresh to strong speeds Wed into Thu, including the Florida Straits.

New England Waters: High pressure will build SE over the waters today, and then pass E of the area tonight. A warm front will lift N across the region later tonight and Thu. A cold front will move gradually SE across the area Thu night into Fri, then move S of the area Fri. The front will stall off the Mid-Atlantic coast Fri night and Sat, and then will lift back N into the waters as a weak warm front Sat night into Sun, then N of the area Sun night. Another cold front will approach the area from the W Sun and move into the waters Sun night.

A powerful Spring storm system will bring a barrage of life-threatening weather including flash flooding and strong tornadoes to portions of the Lower Ohio Valley and Mid-South Wednesday, with the flash flood threat only the beginning of a multi-day catastrophic and potentially historic event. Tornado outbreaks are  expected today for the Mid-South of the USA with multiple intense tornadoes possible.

 

   

Discussion on Atlantic Ocean Currents

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