Climate is a sort of huge ‘machine’. What’s called ‘weather’ is just a small bit of this machine which you and I notice: you know, a tornado, a blizzard, a hurricane , very hot weather or very cold weather. And I bet you know what drives this machine, don’t you? Yes, it’s the sun. Without the sun, there would be no climate, no weather, no people, no penguins, no life. So what’s the difference between climate and weather? This short video helps explain.
The sun warms the air and hot air rises bringing with it moisture from the sea. As the moist air rises, it expands. This makes it cooler and so any moisture in the air condenses to make clouds.
The sun also warms the seas and oceans which makes huge currents of water — a little like winds, but inside the ocean. One of these called the Gulf Stream in the North Atlantic Ocean. This keeps countries in Northern Europe warm even though they are nearer the North Pole than the equator. Another huge current — this time a cold current — affects Chile and Perú in South America. This is called the Humboldt current. It brings lots of food for fish to eat which once made the Peruvian fishing industry the biggest in the world. It also means that many seabirds can live there… including penguins. All these things — the oceans, the atmosphere, the hot and the cold parts of the planet, deserts, rainforest — all depend upon climate and upon the sun.
What is condensation?
The air in the atmosphere contains water vapour which you can’t see. When the air cools to what is called the dewpoint, the water vapour becomes tiny droplets of liquid. It’s called ‘condensation’ and can only take place round ‘condensation nuclei’, tiny particles such as dust. As they get carried higher by air currents, the droplets get colder and absorb still more water from the humid air around them. The droplets get bigger and it is these that forms clouds which, of course, you can see.
What are hurricanes?
Hurricanes are large rotating storms which bring heavy
rains, floods and winds over 155mph in the worst (category 5) ones. They’re
common in the Caribbean region where they occur in a ‘season’ which peaks
in September. They’re also common in other parts of the world wherever there
are warm seas. These storms are also called ‘tropical cyclones’ or ‘typhoons’.
A tornado is a violent rotating thunderstorm. Wind speeds may reach 300mph in the narrow funnel which descends from the clouds and causes a trail of destruction on the ground. Although tornadoes can happen anywhere, they are commonest in the USA which has a ‘tornado season’ in early Spring. Most occur in the midwestern and south central states, sometimes called ‘tornado alley’.
Why rainforests are so important
Rainforests like those of the Amazon and Congo are doubly important. Why? Because they ‘make’ their own climate. The trees soak up rain and evaporate moisture through their leaves to form clouds… you know the rest. They’re important for many reasons, one of which is that if people burn them or cut them all down, the land that’s left is usually poor and the whole climate can change to much hotter and drier. This could happen within a few years because of all the logging and burning that people are doing.
The sun is getting hotter. It is also incredibly old — about 4,500 million years old! One day it will blow up but that won’t be for another 4,000 million years or so. But the Earth’s climate seems to be heating up much much faster than can be explained by the sun making more heat. And the reason is you people and your machines
Almost all machines use oil, gas or coal. All of them produce pollution — you know, the smelly stuff that comes out of car exhaust pipes and factory chimneys, that sort of thing. Much of this is a gas you can’t see called carbon dioxide (CO2). It’s this gas which seems to be the main cause of the trouble.
Pandora’s carbon box
Pandora was a woman who figured in one of the Greek myths. In the myth, the gods gave her a mysterious box. They’d put something nasty in the box and told her never to open it. But she was overcome by curiosity and opened the box. Out flew horrible stuff like plagues, sorrow and misery. She tried in vain to shut the lid but it was too late: the horrors were free.
It’s a little like that with fossil fuels. For millions of years, the planet has been tucking away its Click link for carbon dioxide in the form of coal, oil, limestone. This natural sequestering of carbon and burying it deep in the Earth’s crust has kept the climate machine in balance. Too much carbon means global warming; too little means cooling. Humans have opened the planetary Pandora’s carbon box and let out fossil fuels on a vast scale. Burning them releases the carbon they contained back into the air as carbon dioxide, CO2.
Scientists (called astronomers or cosmologists) who study the sun and stars know this because they can look at millions of other ‘suns’ (the stars) and find out what’s happened to the different types over billions of years.
It’s this heating up which scientists call ‘global warming’ or ‘climate change
A myth is a sort of fairy story. The ancient Greeks made up lots of them over 2000 years ago.
Coral reefs and limestone
Limestone is a rock formed from carbon, oxygen and calcium: calcium carbonate. Most limestone forms when the skeletons of once-living animals like coral turn into rock. When they were alive, the coral polyp animals built their skeletons out of carbon dioxide and calcium. So, like coal-forming swampy forests, they usefully take carbon dioxide out of the air (though it has to dissolve in the seawater first, which it easily does). The ancestors of today’s coral animals have been building vast coral reefs for hundreds of millions of years. These are now limestone rock. Today, as they always have, reefs make nurseries and homes for myriads of living things, so they teem with life. Many people depend on some of this life, like fish. Sadly, pollution and the warming climate are causing many of these giant reefs to die.
‘Sequester’ means to give up for safekeeping, to remove. So carbon is taken out of the ocean-land-atmosphere carbon cycle and sealed away safely.
What happens when you go into a greenhouse on a sunny day? It’s hot, isn’t it? That’s because the glass in the greenhouse traps the heat from the sun. This gas carbon dioxide
does the same in the earth’s atmosphere
. It acts like glass in a greenhouse, doing the same as my feathers do when I’m swimming in the very cold sea: my feathers
keep me warm, the glass in the greenhouse keeps the plants inside warm, and the carbon dioxide and other greenhouse gases keep the planet warm. Without them, we’d freeze. Too much of them means that we boil!
. Because people are burning fuels with carbon in (that’s oil, gas and coal which you use in cars
, power stations
and so on), all this carbon gets dumped into the air
, combined with the oxygen
we all breathe, and so adds to our greenhouse gas problem. And the planet warms more than it should.
Carbon dioxide (CO2) isn’t the only ‘greenhouse gas’ though it is the most common. There are several others. Methane is 21 times more powerful at trapping heat than CO2 and there are other gases made by people which can be thousands of times more powerful.
“The climate is an angry beast, and we are poking at it with sticks.”
– Wallace Broecker
What happens next is not good news for people or penguins. The thing that bothers me is that the ice of the poles is melting. Some of it already is melting fast. The Arctic sea ice get’s less every year and the great frozen continent of Antarctica (my home) is losing ice too. Other seas, like the North Sea, are warming too. This means that fish which need colder waters have to swim north and this can have bad effects on both fishing and seabirds.
As you know, penguins like ice. Without very cold water and ice, we get too hot because, like polar bears, we’re built for cold weather. But for you people, it will be much worse.
For a start, all the ice that melts will start to fill up the oceans and make them overflow on land. And the water itself will take up more space simply because it is warmer. That will make it overflow even more onto the land:
Dr Broecker, of Columbia University, New York, USA, was the first scientist to describe the worldwide ocean ‘conveyor-belt’ currents which partly control climate. These currents ship a lot of heat from the tropics to regions like northern Europe via the Gulf Stream. Without this warmth, northern Europe would be much colder.
Penguins in distress
Adelie Penguin numbers in the Antarctic have shrunk by one third during the past 25 years. This is because there is less winter sea ice where they live.
Warming is 5 times greater than average. Since 1945, the Antarctic Peninsula has warmed about 2.5 degrees C (4.5 degrees F ). Each year’s melting season has gone up by 2 to 3 weeks in just the past 20 years.
Where is the North Sea?
This sea lies between Great Britain on the west side, and Scandinavia on the east. It’s best known these days for declining oilfields and fish stocks.
Polar bears depend for their food on seals. They can only hunt the seals when there is floating sea ice because the seals have breathing holes in the ice where the bears ambush them. The seals also have their pups on the ice. No ice, no seals, no polar bears.
This is called thermal expansion — warmer water takes up more space.
More sea and less land is fine for penguins and for fish, but it’s no good at all for people and other animals that live on the land. Some of the best land for growing food is also the most low-lying. That means it will be flooded first. It also happens that some of your biggest cities, like London, New Orleans
and Bangkok, will get flooded too. Loads of people will go hungry and many more will have nowhere to live. This is very worrying.
The really sad thing is that it will be poor people who suffer most. I think that’s very unfair because it’s the people in rich countries who have been the cause of almost all global warming but it’s the poor
who drown or starve.
What do you think?
Then there’s disease. As the world warms, nasty diseases like malaria
are starting to spread because the changing climate favours the mosquito that carries the disease. air travel: bad for the planet; great for spreading diseasesAir travel is not just a cause of global warming but aids in spreading diseases very quickly just about anywhere. Someone with an illness like TB
may easily pass on the disease
to others during an airplane flight of a few hours. Insects like Click link for videomosquitoes which can carry disease can even ‘hitch a ride’ on flights from one country to another.
Most of New Orleans is actually below sea level! And it did get badly flooded when hurricane Katrina hit in late August 2005.
About 3.2 billion people – nearly half of the world’s population – are at risk of malaria. In 2015, there were roughly 214 million malaria cases and an estimated 438,000 malaria deaths (World Heath Organization). Most of these are in the world’s poorest countries. There are drugs for treating it but the malaria parasite (a tiny protozoan called Plasmodium) has become resistant to almost all of them. Poor people can’t afford them anyway.
TB, short for ‘tuberculosis’ spreads when infected people cough and sneeze. In 2014, TB caused over 1 million deaths. It is a very serious disease because the TB bug is highly resistant to treatment.
In fact, if you were a disease bug looking for a human to infect, an airplane cabin would be the perfect place. Inside, the passengers are sealed into a metal tube for many hours with poor ventilation. Someone with a cold, flu or worse who coughs and sneezes will be (unintentionally) blasting bugs into the air. The bugs float around and get sucked in by other nearby passengers as they breathe. The bugs think it’s great and that’s why people so often ‘pick up’ something like a cold when they fly, packed in to the plane like sardines in a can. This is how diseases like SARS and MERS were spread. There were also some cases of Ebola which made it to North America and Europe during the terrible outbreak in West Africa in 2014. If and when Bird Flu gets going, flying is going to be what transmits it all around the world in just a few days. Scary, isn’t it.
I’m afraid worse is to come: people who study earth’s climate have found that as it warms up, the weather is going to get more violent and unpredictable. Hurricanes, for example, will become more powerful — a big worry for people living in the south of the United States and in the tropical Pacific or Indian ocean areas like the Philippine islands and Bangladesh. Deserts are increasing and places like the Great Plains of America will get drier. Rain will be heavier in other parts of the world so there will be more floods. These things have already started to happen.
What is El Niño?
This is a huge climate ‘event’ during which winds and sea surface temperatures in the tropical Pacific Ocean go into reverse. All kinds of weird weather happens worldwide because of this, much of it very damaging. El Niño events erupt every few years and peak arond Christmas: El Niño (Spanish) means The Child (Jesus). 2015-16 has seen the biggest El Niño episode for some years. Climate change seems to be making El Niño events stronger. More on what happens…
Also called typhoons or cyclones. The image is of cyclone Catarina, taken from the International Space Station. It was the first hurricane seen in the South Atlantic Ocean; March 26 2004, near Brazil (NASA).
On November 8, 2013, Typhoon Haiyan struck the Philippines. It was one of the strongest tropical cyclones ever recorded with wind speeds up to at 285 kilometres per hour (180 mph). Haiyan did terrible damage to several parts of South East Asia, but especially the Philippines where well over 6,000 people were killed. The animation of Typhoon Haiyan is from infrared satellite images (NOAA)
Heavy rains and serious floods have been affecting northern and eastern Europe in recent years. In the summer of 2007, Britain had the worst floods since records began. But much worse was to come. Parts of Britain have had record-breaking quantities of rain during the winter of 2015-16. Large areas have been underwater and many towns have been repeatedly flooded. This is exactly what climate change science predicts: more storms and more heavy rain.
York floods, UK, 2015 (Richard Scott)
What does El Niño do?
In normal years, strong winds (called ‘trade winds’) blow from east to west across the equatorial Pacific Ocean. Among other things, this has the effect of dragging up deep, cold waters off the South American coast. At the west side of the Pacific Ocean, the waters are warm and there is plenty of rain. When an El Niño event (called El Niño Southern Oscillation or ENSO for short) happens, everything goes into reverse. This can mean serious droughts in countries like Indonesia and heavy rain and flooding in other places where it is normally dry. But El Niño affects far more than just the Pacific region. It also causes terrible drought and famine in parts of Africa. El Niño is very complex and causes disturbances and bizarre weather events over much of the planet. It usually lasts about a year, peaking in activity at around Christmas. It also releases a lot of heat into the atmosphere so 2015 was the hottest year on record.
Our planet is getting hotter rather quickly because of greenhouse gas pollution from humans. But there are some people who say it is not
. Can you think who some of these might be? You guessed it! Many of the people who claim climate change is not happening are those who use lots of fuel
, who make things like cars that use lots of fuel
, or actually get the fuel out of the earth: that’s heavy industry, carmakers and the oil
companies. This is called ‘vested interest’. These are people who depend on other people using lots of fuel if they are to continue making money. It’s not surprising that they deny climate change. But it doesn’t make them right!
Just for the record…
Fifteen of the 16 hottest years on record have all been this century, with 2020 looking like it will be the hottest since records began The record temperatures over both land and the ocean surface up to 2020 were accompanied by many extreme weather events such as heatwaves, flooding, severe droughts and massive wildfires throughout Australia. The Greast Barrier Reef, famous for its beautiful corals, was bdaly damaged AGAIN by hot seawater which caused bleaching and the beginning of the end for coral reefs everywhere. Over 70,000 fires burned in the Amazon rainforest which could soon begin to give out more CO2 than it absorbs. Most of the fires were deliberate so farmers could produce more cattle to make into hamburgers, and grow feed for them.
World Meteorological Organization et al. and WWF
The case for climate change – global warming – is now beyond doubt. There is so much evidence from all over the planet. So wouldn’t it be wonderful if everyone agreed to work together to stop using fossil fuels. Well it seems that they may actually do this following the agreements reached at the Paris climate conference in December 2015.
These people are often called ‘deniers’ or ‘sceptics’.
Yes, climate change is real and unfair! But now there’s some good news at last…
The world is getting hotter. And I’m sorry to say it’s all people’s fault.
But it’s not everyone that’s doing it. Mostly it’s people in rich countries — North America, Europe and Australia. They are the ones with energy-hungry lifestyles which guzzle fossil fuels.
Life is not fair!
A child born in the United States will create thirteen times as much ecological damage over the course of his or her lifetime than a child born in Brazil
The average American will drain as many resources as 35 natives of India and consume 53 times more goods and services than someone from China
With less than 5 percent of world population, the U.S. uses one-third of the world’s paper, a quarter of the world’s oil, 23 percent of the coal, 27 percent of the aluminum, and 19 percent of the copper
American fossil fuel consumption is double that of the average resident of Great Britain and two and a half times that of the average Japanese
Source: Scientific American 2012
Poor people like those in most African countries, Asia and Latin America can’t afford to travel all over the place in cars and planes, they don’t have heating or air conditioning in their homes or eat fancy food. Many don’t even have anything more to live in than a one-room shack with no toilet, no kitchen, no running water. These people are not the ones causing global warming. Yet they are the ones who suffer most from climate change caused by the rich. It’s not fair, is it?
As for us other animals, we are innocent too because the only fuel we use is that which we get from our food … so what are you folks going to do about it?
But — at last — people are starting to take serious action on climate change…
In 1988, a group of scientists from many nations began working together to examine the evidence for climate change and make careful suggestions to the world’s governments as to what they could do about it. This group is called the IPCC.
IPCC scientists have studied the climate all around the world. They’ve known for many years that climate change really is happening. They knew that it would be bad for people and much other life. And as more evidence piled in, it became obvious that it is mostly due to humans and their pollution of the atmosphere by burning fossil fuels. So way back in 1992, most of the world’s countries got together at a United Nations (UN) conference in Rio de Janeiro, Brazil. This was called the Earth Summit. Here everyone agreed to start a series of conferences to try and get a worldwide agreement to slow climate change. Most countries soon joined the United Nations Framework Convention on Climate Change..
Kyoto: a lot of hot air? Back in 1997, 192 countries in the world came together in a big conference at Kyoto in Japan. Here they began to try and agree what to do about climate change. Lots of promises were made but countries haven’t been very good at carrying them out. Many people consider Kyoto was a failure. Pollution by greenhouse gases continued to climb.
Since then, the evidence for change has become stronger and stronger. The special computer ‘climate models’ which IPCC scientists had used to predict what would happen are better than ever. The ice sheets in both the Arctic and the Antarctic are melting, in some cases very fast. Sea levels are rising. Temperatures are rising, especially in the Arctic and Antarctic. Glaciers on other mountains of the world are melting very fast — especially in the tropics. Animals and plants which like cooler conditions are moving away from the overheated tropics towards the poles. Storms are getting stronger, with damaging winds and heavy rain causing serious flooding. All these things are predicted by climate models. And really sadly, most of the world’s coral reefs, including the Australian Great Barrier Reef, are dying because of unusually hot seas.
The COP 21 Paris Agreement
Since Kyoto, there have been more climate conferences. The latest and greatest of these conferences took place in Paris, France, at the end of 2015 (COP 21). At last, everyone from all the 195 countries attending the conference agreed that NOW is the time to take climate change seriously, so they set up a system to do it. The aim is to keep the global temperature rise to below 2°C.
This is the first time there has been general agreement about what to do and how to do it. Well done humans, I say! It’s called the Paris Agreement. But it won’t be easy because the entire global economy is hooked on fossil fuels. So the road ahead may be rocky but it is passable. It has to be!
So now it’s up to you humans to undo the damage that has been done to the Earth’s climate system by burning fossil fuels. Obviously this hasn’t been done by you kids but unfortunately, it is you – your generation – which will have to slam on the fossil fuel brakes hard or live with a wild climate which will be very unpleasant indeed for much of life on Earth, especially human life… not to mention penguins and polar bears! But I think you humans are incredibly clever and resourceful, and I think you will solve the problems ahead. The next really important UN Climate Change Conference (Conference of the Parties, COP 26) — because of the COVID-19 virus pandemic — has been postponed for a whole year. Glasgow, Scotland’s largest city, will host this in November 2021.
Okay, now that you know lots about climate change, how about trying my Hot Earth quiz to see how much you really know! I’ve made a global warming crossword puzzle here. If you can’t do it, you probably haven’t read my guide!
Now try using this clever tool to see how you would choose to reduce CO2 emissions to 20 per cent of 1990 levels. It’s fun to use and gives you an idea of the difficult choices you people have to make to avoid dangerous climate change.
But it’s not all doom and gloom! Check out what you and your friends, family and schools can do. You CAN make things better. See below for things YOU can do… !
What is the IPCC?
The Intergovernmental Panel on Climate Change. It was set up by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) in 1988. The idea was to provide the world with a clear, up-to-date scientific view on climate change. There are 195 countries which are members of the IPCC. The latest IPCC view on the state of the world’s climate is the Fifth Assessment Report (2014)
What is the UNFCCC?
This is an international treaty, the United Nations Framework Convention on Climate Change. The idea is that the world’s nations (called ‘the Parties’) come together to work out what they can do to limit climate change and to help poor nations which are already suffering some of the worst effects. The UNFCC organises international conferences – called Conferences of the Parties (COP). The latest of these, COP 21, took place in Paris, France, in late 2015.
The Paris Agreement at COP 21
The 195 countries attending the conference agreed to a global pact, the Paris Agreement. The aim is to reduce their carbon output (= carbon emissions = atmospheric carbon pollution) “as soon as possible” and to do their best to keep global warming “to well below 2 degrees C”. Each country that signs up to the agreement has to set a target for emission reduction, but the amount will be voluntary. There is no means to force any country to comply. So the agreement depends more on goodwill and a general agreement that global climate change is happening. People are all in this together and so have to work together to preserve climate stability. Whether this will work remains to be seen and may depend upon you kids, as you get older, hassling your country’s governments and making sure they are sticking to their commitments. It’s not going to be easy!
What does this road ahead involve?
There has to be a drastic cut in carbon emissions by everyone everywhere to try and stabilise the climate. There also has to be adaptation and mitigation. ‘Adaptation’ means that people will have to change their lifestyles and adapt to the changing climate. ‘Mitigation’ means that help will have to be given by rich countries to poor countries whose peoples are being harmed by the changing climate