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Climate change.

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Presentation on theme: "Climate change."— Presentation transcript:

1 Climate change

2 What is climate? Climate is not the same as weather
Weather is more short term – it is the temperature, cloudiness, humidity, etc. at a given time, based on what happens each day in our atmosphere Climate is the average pattern of weather for a particular region over time Explain that climate is not the same as the weather. Weather is more short term - it is the temperature, cloudiness, humidity, etc. at a given time, based on what happens each day in our atmosphere. So on a given day the weather could be cold, cloudy and rainy in one place in the world, and hot and sunny in another - that’s the weather. Climate, on the other hand, is the average pattern of weather for a particular region over time (usually over more than 30 years). While the weather can change in a matter of hours, climate takes hundreds, thousands or even millions of years to change. Climate also includes seasons and weather extremes – for instance, some areas of the world have climates which are more likely to lead to the occurrence of hurricanes at certain times of the year. June to October is hurricane season in Florida, USA. Climate also includes: Seasons Weather extremes (hurricanes, droughts, floods, etc.)

3 What is climate? Earth is a system in which the land, water and atmosphere all work together to create the particular climate of a region Two of the most important factors determining an area's climate are air temperature and precipitation Variations in any of the components of the Earth’s system will result in different climates – this is why deserts are so different to wetlands! Explain to students that planet Earth can be viewed as a ‘system’, with different components working together to create the climate of a region. The combination of land, water and atmosphere all contribute to the creation of a particular climate in a given region. Two of the most important factors determining an area's climate are air temperature and precipitation. Variations in any of these components result in different climates, which is why there are so many types of climate on Earth, from hot, dry deserts and warm, moist rainforests to cold, grassy tundra. Ask the students if they can name any climate types (Note: these can be the basic types, such as polar, temperate, tropical, etc.).

4 Climate types Explain that this map shows some of the different types of climate found across the globe. Here, there are six main climate types: Polar Temperate Arid Tropical Mediterranean Mountains However, note that scientists sometimes split the climatic regions slightly differently, as there are different ways of classifying climates. The climate types may be given different names - for example, areas with an arid climate are sometimes referred to as having a dry climate, and mountains can also be referred to as uplands. The main, overarching climate groups are also often split further into many more specific climate types. For instance, Polar could be further split into ice caps and tundra, while Tropical is sometimes split into tropical wet and tropical wet and dry. Much of the USA is classified as having a temperate climate, but this can be split down further, with Florida (on the east coast) having a humid subtropical climate. Explain that you will now look at the processes involved in creating the Earth’s climate. Before moving to the next slide, ask the students if they know where the Earth gets its energy and heat from.

5 Greenhouse effect Heat from the sun warms the surface of the Earth
Some of this heat is absorbed by the Earth, and some is radiated back out towards the atmosphere Naturally occurring gases in the atmosphere, known as greenhouse gases, act like an insulating layer and absorb much of this heat Some of this absorbed heat is then re-radiated back towards Earth This process is called the greenhouse effect, as the gases act in a similar way to the glass of a greenhouse Explain that the heat from the sun warms the Earth’s surface – about 0.1% of the energy radiated by the sun passes through the atmosphere and reaches the Earth’s surface. Some of this energy is then absorbed by the Earth’s surface and some is radiated back towards the atmosphere. Naturally occurring gases in the atmosphere, known as greenhouse gases, act like an insulating layer, absorbing some of the heat and preventing it from passing through back to space. This heat is then re-radiated by the gases in different directions, including back towards Earth. This is known as the greenhouse effect, because the gases in the atmosphere act much like the glass of a greenhouse, trapping the heat and keeping Earth (or the plants in the greenhouse!) warm. This process is essential to life – think how cold it would be if this didn’t happen! However, human activity is adding to the natural levels of greenhouse gases and increasing the greenhouse effect. More energy is being reflected back down to earth. VIDEO Without it, the Earth would be extremely cold!

6 Greenhouse gases There are several different gases in the atmosphere which are responsible for the greenhouse effect – these are called greenhouse gases These gases occur naturally in the atmosphere Can you name any greenhouse gases? Carbon dioxide Chlorofluorocarbons (CFCs) Explain that there are several different gases in the atmosphere which are responsible for the greenhouse effect, and state that these all occur naturally in the atmosphere. Ask if the students can name any of them: Carbon dioxide, methane, ozone, water vapour, nitrous oxide and chlorofluorocarbons (CFCs). Tell the students that you will be revisiting some of these gases later in the lesson. Reiterate that these are naturally occurring gases in the atmosphere, and that we’re reliant on them for keeping the Earth warm. However, human activity is increasing the greenhouse effect – ask the students if they know how. Methane Water vapour Ozone Nitrous oxide

7 An increase in greenhouse gases
Human activity is increasing the concentration of these naturally occurring greenhouse gases in the atmosphere This disrupts the natural balance of the system, causing changes in Earth’s climate One of the consequences of this imbalance is global warming Explain that the problem lies with human activity producing large quantities of these gases – this leads to an increase in the levels of these gases in the atmosphere, and disrupts the natural balance of the system. Ask the students if they know what the consequences of this imbalance are. Explain that one of the consequences is global warming, and that you will now explain the term.

8 Global warming An overall increase in the Earth’s surface temperature – the Earth’s temperature has risen by about 0.75oC globally This long-term increase in the Earth’s surface temperature is referred to as ‘global warming’ Using climate change models, some scientists have predicted that the Earth’s average temperature will increase by 3 to 5oC over the next 100 years One of the effects of this increase in greenhouse gases is an overall increase in the Earth’s surface temperature – the Earth’s temperature has risen by about 0.75°C globally. This long-term increase in the Earth’s surface temperature is referred to as ‘global warming’. Using climate change models, some scientists have predicted that the Earth’s average temperature will increase by 3 to 5°C over the next 100 years. Global warming is one of the main consequences of an increase in greenhouse gases, and it is a very serious one, but there are several other important effects. To cover all of these effects, the term climate change is often used…but what is it? Increase in global temperatures simulator - However, global warming is not the only consequence of an increase in greenhouse gases – because there are many effects, the term ‘climate change’ is often used

9 What is climate change? Climate change is a long-term change in the Earth’s climate or in that of a region on Earth  While climate change is a natural process, this term now usually refers to the relatively rapid changes caused by human activities RECAP: Introduce the concept of climate change: Climate change is a long-term change in the Earth’s climate, or in the climate of a region on Earth. Reiterate that a change in climate is very different to having a couple of days of unexpected weather. Explain that, while climate naturally changes over time, the change is usually very slow. The term ‘climate change’ now usually refers to changes in the climate caused by human activities. Within scientific journals, this is still how the two terms are used. Global warming refers to surface temperature increases, while climate change includes global warming and everything else that increasing greenhouse gas amounts will affect. Global warming refers to surface temperature increases Climate change includes global warming, but also includes everything else that an increase in greenhouse gas concentrations will affect Can you name any other effects of climate change?

10 Other consequences of climate change
Warming oceans – they absorb 80 percent of the heat Rising sea levels – sea levels have risen by about 17 centimetres globally Ocean acidification – more carbon dioxide from the atmosphere is being absorbed into the ocean, making the water more acidic There are more effects to climate change than just an increase in surface temperature. Climate change is having a big effect on the world’s oceans: The oceans are warming as they absorb about 80 percent of the heat, with the top 700 metres of the ocean showing the greatest warming. Sea levels have risen by 17 centimetres since 1900, and the rate at which sea levels are rising is increasing ( Ocean acidification is the process whereby the pH of the oceans is decreasing (becoming more acidic) as more carbon dioxide from the atmosphere is being absorbed by the oceans. The carbon dioxide content of the Earth’s oceans is increasing by about 2 billion tonnes per year, which has increased ocean acidity by about 30 percent.

11 Other consequences of climate change
Declining Arctic sea ice - the Arctic sea ice has been declining since the late 1970s Shrinking ice sheets - In Greenland and the Antarctic, ice sheets have started to shrink Extreme weather - In the last decade there were three times more weather-related natural catastrophes Arctic sea ice has been declining since the late 1970s, reducing by about 0.6 million square kilometres per decade - an area around the size of Madagascar. Average Arctic temperatures have also increased at almost twice the global average rate in the past 100 years. In September 2012, the Arctic sea ice was at the smallest extent ever recorded ( simulator ( The Greenland and Antarctica ice sheets, which between them store the majority of the world’s fresh water, have both started to shrink. In the last decade, there were three times more weather-related natural catastrophes in the world than in the 1960s, including heat waves, floods, droughts and forest fires. More intense and longer droughts have also been observed over wider areas since the 1970s, particularly in the tropics and subtropics.

12 Causes of climate change
Scientists agree that the main cause of climate change is human activity, which increases the levels of greenhouse gases in the atmosphere, magnifying the ‘greenhouse effect’

13 Greenhouse gases – which are the main contributors?
Human activity is increasing the level of several different greenhouse gases. How much each of these gases affects climate change depends on three factors: - How much is being produced - How long the gas stays in the atmosphere - How powerful the gas is at trapping heat Human activity is adding several different types of greenhouse gases to the atmosphere. How much these gases affect climate change is dependent on three different factors: How much is being produced - the amount of gas being produced by humans varies greatly between gases. The main greenhouse gas which people are adding to the atmosphere is carbon dioxide. How long the gas stays in the atmosphere - different greenhouse gases stay in the atmosphere for different amounts of time. Some will only stay for a short period of time whereas others stay in the atmosphere and affect the climate for much longer periods of time. Carbon dioxide stays for 50 – 200 years in the atmosphere compared to methane which only stays for 12 years. How powerful the gas is at trapping heat – different greenhouse gases trap different amounts of heat. One pound of methane traps about 25 times as much heat as one pound of carbon dioxide. The two greenhouse gases of most concern are methane and carbon dioxide. Explain that you will look at these in a little more detail now.

14 Carbon dioxide The main source of carbon dioxide is the burning of fossil fuels Fossil fuels are used to: - Drive cars - Provide electricity - Heat our homes with oil or gas Deforestation - Plants remove carbon dioxide from the atmosphere by photosynthesis – a process where plants use carbon dioxide and sunlight to produce energy - If trees are cut down, the amount of carbon dioxide being removed from the atmosphere is reduced Carbon dioxide is the main greenhouse gas being added to the atmosphere by human activity. Driving a vehicle, using electricity or heating our homes requires energy. A lot of this energy is provided by burning fossil fuels (coal, oil, natural gas). When fossil fuels are burned, carbon dioxide is released into the atmosphere. Other human activities, such as deforestation, are making the problem worse. To produce energy, plants photosynthesise - photosynthesis is a natural process which removes carbon dioxide from the atmosphere. When trees are cut down there are fewer plants to remove carbon dioxide from the atmosphere. If the trees are burned to clear the land, this amplifies the effect further, as it releases the carbon which is ‘locked up’ in the wood.

15 Methane Methane is produced naturally:
By living animals, such as cows! In areas of waterlogged soil By rotting plants and other organic material However, human activities are increasing the levels of methane being released into the atmosphere in several ways: - Industry – methane is produced during the production, processing, storage and distribution of natural gas - Increase in cattle rearing – cows naturally produce methane, but an increase in cattle rearing for milk and beef has increased the amount of methane - Rice paddies – rice is grown in flooded land known as rice paddies. There has been an increase in the number of rice paddies due to an increasing population, which has led to higher levels of methane being released - Landfills – as waste decomposes in landfills, methane is produced Methane is the second most prevalent greenhouse gas in the USA. Methane is produced naturally from a range of sources: - Living animals as part of their normal digestive process - Areas of waterlogged soil - Rotting plants and organic material release methane Despite being a naturally occurring gas, over 60 percent of total methane emissions globally come from human activity. Human activities are releasing methane in a range of different ways: Industry: Methane is the main component of natural gas - during the production, processing, storage and distribution of natural gas, some methane is emitted. Agriculture: Domestic livestock produce large amounts of methane. As humans raise domestic livestock for food, the emissions from these animals is considered to be a result of human activity. Globally, this is the biggest contributor to methane emissions. Rice paddies: Rice is grown in flooded land known as rice paddies. There has been an increase in the number of rice paddies due to an increasing population, which has led to higher levels of methane being released. Landfills/ Waste: As waste decomposes in landfills, methane is generated. The organic material in landfills gets trapped in conditions with no oxygen, which produces large amounts of methane.

16 Effects of climate change on animals and plants
Scientists predict that man-made climate change could contribute to a mass extinction of wildlife in the near future Climate change affects many species of animals and plants from a range of different habitats and climate types Many plants and animals have specific habitat requirements and need certain climate conditions to survive, and these are being altered by climate change Melting polar ice caps, increasing acidification of the ocean, and loss of land due to rising sea levels are just a few examples of how climate change is affecting species and their habitats Most plants and animals live in areas with very specific climate conditions, such as temperature and rainfall patterns, that enable them to thrive. Any change in the climate of an area can affect the plants and animals living there, as well as the entire ecosystem Climate change is also causing some migratory species, including many birds, to leave their wintering grounds for breeding areas earlier in the year, leading to competition with resident species for food and nesting areas. As ice melts in the Polar Regions, polar bears and emperor penguins are losing vital habitats. The ocean is also becoming more acidic, which is killing many corals. Species that live or breed on low-lying remote islands, like marine turtles, are threatened by rising sea levels and extreme weather, and many plants, which cannot move to find new habitats, are disappearing from parts of their range due to drought and higher temperatures This will be looked at in more detail in the activity. Explain to the students that you will now look at three case studies to investigate the impacts of climate change on different species.

17 Case study 1 - Polar bear Climate change is the biggest threat to polar bears Dependent on sea ice for survival Need ice as a platform to hunt seals and to breed Climate change is the biggest threat to the survival of polar bears. The Arctic sea ice is declining (reducing by an area the size of Madagascar per decade) due to climate change, with sea ice losses in 2012 breaking all previous records. Polar bears are dependent on sea ice for survival because they use the sea ice as a platform from which to hunt seals and as a breeding ground. As the polar bears’ access to prey is being reduced, they are being forced to spend more time on land, relying on their stored fat reserves. Less food means bears will give birth to fewer, smaller young. Another problem caused by a reduction in sea ice is that polar bears must increasingly travel across open water, leading to greater mortality of cubs that are unable to swim long distances. Individuals are having to travel longer distances across open water – this uses up vital energy reserves

18 Case Study 2 - Clownfish and anemones
Clownfish depend upon sea anemones for protection from predators Sea anemones are under threat as they are normally found on coral reefs, which are globally declining due to climate change Interspecific interactions are when two different species living in the same ecosystem interact. This includes predation, competition, commensalism (where one benefits and the other isn’t affected), parasitism (organisms that live on or in a host organism - the parasite benefits from this arrangement, but the host suffers as a result) and mutualism (an association between two organisms of different species where both benefit ). Clownfish and sea anemones have a mutualistic relationship. Clownfish are dependent on sea anemones for protection. While most fish avoid sea anemones due to the anemones’ poisonous stings, clownfish have developed an immunity to these stings and so can use this for their own protection from their predators. In return, the clownfish keeps the anemone in a healthy state and prevents the sea anemones from being attacked by other species which are also immune to the sting, such as angelfish and sea turtles. The biggest threat to clownfish is the loss of their sea anemone habitat. Sea anemones are normally found on coral reefs, which are globally declining as a result of climate change If CO2 levels reach 450ppm (due to occur by at current rate of increase), reefs will be in terminal decline. A loss in sea anemones will lead to a decrease in clownfish populations

19 Case Study 3 - Ruby-throated hummingbird
Migratory birds rely on environmental signs to let them know when it is time to migrate Ruby-throated hummingbirds winter in Central America, and then migrate hundreds of kilometres to breed in North America Research has shown that changing climate in the wintering grounds is causing the hummingbirds to start their migration to North America up to 18 days early Migratory birds rely on environmental cues to let them know when it is time to migrate. For more advanced/older students, ask them to think of an example which links dependence on specific environmental cues and interspecific interactions? Flowers and pollinators – Flowers rely on pollinators, such as bees, to pollinate them and reproduce, while the pollinators rely on the flowers for energy-rich nectar. Flowers begin to bloom as a result of environmental cues. However, with an ever-changing climate, flowers are beginning to open earlier than normal in some areas. This means that, when the bees emerge, the two lots of species are not properly synchronised, and there may not be enough food for the bees (the flowers may have died), and less pollination occurs, meaning that there will be fewer flowering plants the following year. Pollinators are also extremely important to human food production, so if their survival is at risk as a result of climate change (as well as from other threats such as disease and pesticides), this could have a serious impact. This could mean arriving in the breeding areas before food and nesting material is available, or before the temperatures are suitable for survival

20 Activity Climate change is affecting species both directly and indirectly. We are now going to play a game to learn about the different ways in which species are being affected by climate change. Read the factsheet about how ten different species are affected by climate change. Mix the cards up and place them face-down in a grid of four cards by five cards. Take it in turns to turn over two cards and see if they match – you must match a text card with the relevant picture card. If they match, you keep the cards and get another go. If they don’t, turn the cards back over, keeping them in the same place. It is then your opponent’s turn. The winner is the person who collects the most cards. Climate change is affecting species in a range of different ways – habitat requirements, food availability, competition, etc. The students are now going to play a game of memory to learn about how different species are being affected. The students have to pair up the appropriate species (represented by an image card) with how climate change is affecting them. Firstly, explain the aim and rules of the game to the class. Aim: to pair up each species card with the correct climate change effect card. Place the cards face down on the table. Take it in turns to pick up two cards. Look at the two cards. If you have turned over an image and text card, read the text to see if you have a match (you can check the factsheet if you are unable to remember the effect on each species). If you pick up two text cards, read both and remember where the cards are. If you find a match, keep the cards and have another go. Keep playing until all pairs have been collected. The winner is the student with the most cards.

21 How you can help! There are many things you can do to help:
Walk or cycle more Turn lights and other electric devices off Reduce, Reuse, Recycle Eat less meat Spread the word! One of the main contributors to climate change is burning fossil fuels to provide energy. You can help reduce your use of energy from burning fossil fuels by: Walking or cycling instead of getting driven in a car, as vehicles need fossil fuels to run. Turn lights off when you leave a room, and turn off electric devices at the plug when you are not using them. Reduce, Reuse and Recycle - creating new products requires energy which produces carbon dioxide. Reduce - fewer products will have to be made, which in turn reduces the energy required Reuse - throwing away products wastes the energy which was used to create them and transport them Recycle - less energy is needed, so less carbon dioxide is produced, when products are recycled One of the main ways human activity is increasing methane levels is through cattle rearing. If you reduce the amount of meat you are eating, it will reduce the amount of methane being released. And most importantly, you can help by spreading the word – let other people know about climate change and what they can do to help. Find a way to support conservation where you live, and support a conservation organisation working to safeguard species at risk from climate change.

22 Summary Climate change is a long-term change in the Earth’s climate or in that of a region on Earth, but now usually refers to changes caused by human activities Humans are adding more greenhouse gases to the atmosphere which is amplifying the greenhouse effect Some species are more affected by climate change than others There are things you can do to help reduce the effects of climate change!


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