Category: Geography

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Geography Weather

Cloud, Sunshine and a cool Breeze

polar continental air
synoptic chart 6th June 2023

Were you lucky enough to have blazing sunshine through the half term holiday, or were you sitting under a blanket of cloud? 

Whichever, the cool wind and the distribution of cloud were a lovely case study of Polar continental air. 

With High pressure sitting to the North of Scotland, and winds blowing clockwise around it, the typical pattern of cloud forming over the western side of the North Sea, spreading onto the eastern side of Scotland and England, persisted for many days. One some days, the cloud was thin enough for most to evaporate during the day, on others, the cloud persisted. 

Having come from Scandinavia or Siberia, the air was cool. To identify the source of the air, simply pick an isobar that crosses the UK, and follow it back to see where the air has come from, remembering that the wind blows approximately along the isobars, in a clockwise direction around High pressure. 

polar continental air
More about air masses
Categories
Climate Change Geography Secondary Teaching

New IPCC linked teaching resources

 
We are delighted to have worked with the Royal Geographical Society to produce more climate change teaching resources for A Level geography. These are based on the IPCC Working Group II (Impact, Adaptation and Vulnerability) and WGIII (Mitigation) reports. 
 

Energy Security in Africa

  • The focus of these resources are to explore climate change and energy security in Africa.
  • Hydro electric power has been identified as a more sustainable way for Africa to achieve energy security in the future.
  • Throughout the continent of Africa there are already many hydroelectric power stations, with many more planned over the coming decades.
  • Climate change could potentially impact upon these plans. These resources focus upon that relationship.
 Lesson and Homework Resources
Africa- hydropower IPCC

Climate Change in Africa

Africa is one of the lowest contributors to global greenhouse gas emissions, yet key development sectors are already experiencing widespread losses and damages attributed to human-induced climate change.

Students complete a knowledge organiser. 

Africa - IPCC climate change impacts

Extreme Heat in Urban Africa

Climate change has increased heat waves (high confidence) and drought (medium confidence) on land, and doubled the probability of marine heatwaves around most of Africa.

Heat waves on land, in lakes and in the ocean will increase considerably in magnitude and duration with increasing global warming.

Most African countries will enter unprecedented high temperature climates earlier in this century than generally wealthier, higher latitude countries, emphasising the urgency of adaptation measures in Africa.

Lesson and Homework resources

IPCC extreme heat in urban africa

Wildfire

Wildfire is a natural and essential part of many forest, woodland and grassland ecosystems, killing pests, releasing plant seeds to sprout, thinning out small trees and serving other functions essential for ecosystem health. Excessive wildfire, however, can kill people, the smoke can cause breathing illnesses, destroy homes and damage ecosystems.

Students complete a knowledge organiser. 

All Our Resources Based on the 2021/ 2022 IPCC Report
Categories
Climate Change Geography Science Teaching

Resources for COP27

COP27

We have produced some curriculum linked resources for schools to use in the build up to and during COP27 this year.

For geography teachers: a 11-14(+) resources looking at population growth, pyramids, urbanisation and the climate impacts of construction.

For maths teachers: an 11-14 or possibly Core maths resource applying Pythagoras’ theorem to the problem of efficient road construction.

For science (physics) teachers: a 13-16 resource looking at energy transfer and electricity production in the Benban solar farm.  

Access the Resources
Categories
Extreme weather Geography Secondary Weather

Storm Eunice and Generic Case Study Template

Storm Eunice cloud and wind

We have created a new worksheet which allows students to collect information and create a case study of a named UK storm. As part of the worksheet, students collect and annotate weather chart and other information about the storm including weather warnings. 

Storm Eunice is given as a worked example. 

Categories
Geography Schools Secondary Teaching Weather

New Films: Air Masses and the ITCZ

polar maritime air mass

We have made two new explainer films which can be seen on YouTube:

An Introduction to Air Masses

All About the InterTropical Convergence Zone (ITCZ)

 
global rainfall patterns
Categories
CPD Geography Schools

GeogPod podcast

geogpod

Sylvia Knight, Head of Education at the Royal Meteorological Society was in conversation with John Lyon for the Geographical Association’s GeogPod podcast series. Their conversation centres on the COP26, climate change. the IPCC and some of the resources teachers can use in the classroom. 

 
Categories
CPD Geography Schools Secondary

Resources Highly Commended by SAGT

SAGT award

We are delighted that our “Weather and Climate: a Teacher’s Guide” resource has been awarded a Highly Commended in the Book Category for this year’s Scottish Association of Geography Teachers (SAGT) Publishers’ Awards.

Categories
Blog Geography Secondary Teaching Weather

Air Masses

polar maritime air mass

In this article we explore air masses – the idea that, by looking at where our wind is blowing from, and what has happened to the air in the wind on its way to us, we can begin to understand why we’re getting some particular weather.

We live on an island, and the weather can come at us from any direction, although in practice, it comes from some directions more than others  – this wind rose shows the direction the wind was recorded coming from at Heathrow airport, near London. The longer the bar, the more often the wind came from that direction, so you can see that our wind comes from between southwest and west most often.

Lets take a step back and remember that warm air rises – whether that’s the air being heated in a hot air balloon or the air above a radiator (watch a simple demonstration).

What happens to the rising air? As it rises it cools. Cloud and rain are caused by warm air rising, warm air rising is called convection (watch a simple demonstration).

You can often see convection going on in the atmosphere – you get puffy cumulus clouds, with flattish bases and puffy tops where the cloud is bubbling up.

clouds

More generally, Clouds form when there is more condensation going on than evaporation in the atmosphere.

The colder it is, the less evaporation happens – so cloud forms when the air cools.

This isn’t just when warm air rises.

Now we can think about air masses, they are classified according to where they have come from, and what they have passed over:

UK air masses

One air mass generally covers the whole country.

However, it can bring different weather conditions to different places. For example, Tropical continental air can carry Saharan dust, but it mostly falls on the south of the UK – there isn’t much left in the air by the time it reaches Scotland.

Lets consider Polar maritime (Pm) air first (click on the map to start the animation):

Polar maritime air comes towards us from further North in the Atlantic. It starts cold, but is slowly warmed by the ocean below as it travels over progressively warmer water. It also picks up moisture from the ocean. 

As it is warmed, it becomes more unstable and inclined to rise, leading to convection and puffy Cumulus clouds, mainly over the ocean. As the air hits land (the western coast of Ireland, Wales, Scotland and England) the air, which was already inclined to rise, is forced up a bit more – forming more cloud, and giving rise to rainfall. 

Polar maritime air, our dominant air mass, brings cloud and rain to the west of the UK and relatively dry air to the east. 

This satellite image is typical of Pm air – you can see the puffy cumulus clouds over the ocean, and the belt of cloud over the western side of the country.  

Returning Polar maritime air (rPm) is air which is Polar in origin but which swings round to hit the UK from the west or even slightly south of west – but if you were to follow its path back, you would see that it was Polar. 

Arctic maritime (Am) air is extreme Polar maritime air, coming down to the UK straight from the north, over the Arctic ocean. It tends to bring wintry weather to Scotland and isolated snowy showers further south, triggered by air rising over the local orography. 

An Am case study. 

Polar continental (Pc) air will also be cold to start with and get progressively warmer as it moves south, so you would also expect convection. However, the air will be very dry as it passes over continental Europe, so little cloud will form. The UK is a set of islands though and to reach us, the air must pass over the North Sea, picking up water vapour as it does so. The cloud and precipitation (typically snow in winter) it brings therefore primarily affect the east coast. The longer the path it takes over the North Sea, the more precipitation there will be. 

This satellite image is typical for Pc air – you can see the cloud free areas immediately to the west of the land masses, with cloud forming further east (ignore the front to the west of the UK and Ireland).

Another Pc case study. 

Of course, the characteristics of the air masses can be very different in the summer and the winter. Siberia, for example, is extremely cold in winter but relatively warm in summer – so a polar continental air mass can bring us bitterly cold weather and heavy snowfall (for eastern counties) in the winter, but much warmer weather in the summer.

The processes at work in Tropical maritime (Tm) air are a bit different. This is warm air, which is being cooled from below as it moves north. You therefore wouldn’t expect any convection with air rising, cooling and forming cloud. However, the air is being cooled just by moving north and so eventually may reach the temperature at which cloud forms – flat, featureless sheets of stratus cloud because, on the whole, the air is staying at the same level.

As it is maritime air, there is plenty of water vapour available to form cloud droplets. The processes which give us big, fat raindrops are mainly associated with the vertical air motion and circulations in cumulus clouds. So Tm air at best gives a persistent drizzle.

The satellite image below shows the extensive sheet of stratus cloud over the Atlantic associated with Tm air.

We rarely experience Tropical continental (Tc) air – air that flows up from the Sahara over continental Europe.  This is the warmest and driest air we can get – any moisture picked up over the Mediterranean will be rained out before it reaches us.

Tc air gives clear skies, as you can see in the satellite image below – again ignore the front to the west of the UK. In the summer, this can mean that some areas get particularly warm – maybe because of their colour (dark) or aspect (facing the Sun) – giving rise to late afternoon localised thunderstorms

A front is where two air masses meet. In the UK, the weather fronts associated with depressions usually separate polar and tropical maritime air.

If there is a front, then different parts of the UK can be experiencing different air masses. The weather on the fronts themselves is more extreme. 

Look out of the window now – what cloud types can you see? Does that tell you anything about where the air is coming from? You can have a look at earth.nullschool to see if you are right.

 

 

Categories
Climate Change Extreme weather Geography Secondary

New Teaching Resource – Salt Marsh Evidence

We have just added a new resource to our Weather and Climate: a Teachers’ Guide collection in the Changing UK Climate section. 

The resource provides students with source material, graphs and maps to allow them to make a poster explaining how salt marshes can protect coastal areas from the impact of rising sea levels. 

Steart Marshes – designed for adaptation to climate change.

Categories
CPD Geography Teaching

Welsh Translation of Teachers’ Guide

welsh weather and climate

We are delighted to have been supported by the WJEC/ Eduqas, who have translated our Weather and Climate Teachers’ Guide for 11-14+ geography teaching into Welsh – Tywydd a Hinsawdd: Canllaw i Athrawon and made it available to schools for teaching across Wales. 

The full resource, together with background information for teachers and lesson resources can be found on MetLink. 

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Weather and climate resources and events for teachers