Temperatures & Trees Campaign
Lesson 1: What is climate change?
Earth’s Atmosphere
Image: NASA
Our atmosphere is a thin layer of gases (100 km thick).
It extends from the surface of the Earth, to the edge of space.
It makes Earth habitable!
Without our atmosphere, we would be exposed to harmful radiation from the sun and the extreme coldness of space.
How the atmosphere acts as Earth’s protective shield to protect us from the vacuum of space:
Did you know?
The moon does not have an atmosphere. Because of this, it can get up to 120° C during the day and
-130°C at night.
4. It contains oxygen, which we need to breathe.
The atmosphere (the air we breathe) is made of:
Greenhouse Gasses
What are greenhouse gases?
Greenhouse gases are gases in the atmosphere that absorb heat radiating from the Earth and re-emit it. It traps heat close to the Earth’s surface similar to how glass panels trap heat inside a greenhouse.
Examples of greenhouse gases:
Click here
to watch a video about the greenhouse effect
Greenhouse gases are not inherently bad! They occur naturally in the atmosphere and help keep the Earth warm and habitable.
HOWEVER, human activities have increased the amount of greenhouse gasses like carbon dioxide (CO2) and methane (CH4), leading to more heat being trapped in the atmosphere than normal – i.e., higher temperatures than normal.
Note: Naturally released CO₂ is part of the Earth's carbon cycle, so most of it is reabsorbed and does not significantly impact the climate.
�However, human activities release extra CO₂ that is more than the Earth can absorb, leading to climate change.
Important definitions
Weather vs. Climate
An easy way to remember it:
Climate is what you expect (e.g., dry summers), and weather is what you get.
Describes how the atmosphere behaves over a short time.
Timescale: Minutes – Weeks
Examples:
“It’s raining.”
“It’s meant to be 25°C on Friday.”
Weather
The AVERAGE weather for a region over a long time.
Timescale: Seasons – Millenia
Example:
“The wet season normally starts in November.”
Climate
Activity
Can you tell whether these statements refer to weather or climate?
Weather
Climate
or
Weather
Climate
or
Weather
Climate
or
Weather
Climate
or
Global Warming vs. Climate Change
Refers to the gradual increase in Earth’s average temperatures.
Why? Due to the greenhouse effect.
Result: Increased average temperatures, melting glaciers, rising sea levels.
Global Warming
(Both can occur naturally and due to human influence)
Global Warming vs. Climate Change
Refers to long-term changes in regional weather patterns.
Why? Due to disruption of the natural systems (greenhouse effect, melting glaciers, ocean temperatures, habitat destruction, etc.).
Result: Changing climates (rainfall, wind, temperatures), more extreme weather events, global warming.
Climate Change
Takeaway: The number of very wet days in Ireland is expected to increase in the future.
*Global warming is just one aspect of climate change
Why words matter
One of the main reasons people don’t believe in climate change is because they confuse it with global warming.
Is global warming happening? Yes! Climate data shows us that AVERAGE temperatures are increasing over Earth as a whole (Global Warming).
Does this mean that you can’t experience cold days or extreme cold events? No! While temperatures are raising on average, global warming is just one part of the climate change story. Climate change impacts different regions differently.
The term ‘Global Warming’ does not necessarily describe the weather that people are experiencing at any given time. This is why climate scientists are using ‘Climate Change’ instead, since it avoids confusion and may help explain severe weather conditions such as snow in unexpected places or at odd times of the year.
Climate change in the past
How do scientists know what the climate was like thousands to millions of years ago?
Click on the
to watch a short video about each method
Examples of natural climate change
Scientists have strong evidence that climate change has happened before in Earth’s history. Here are some key examples:
So climate change can happen naturally!
Click on the
to learn more
Then why are scientists blaming us for current climate change?
Climate change is happening faster today than ever recorded before in history and scientists are linking it to our carbon emissions!
Source: NOAA
Remember: Scientists are not blaming you personally – they are observing patterns and recommending ways to change the outcome.
We cannot change the past but we CAN change our future!
What is causing climate change now?
Fossil Fuels
What are fossil fuels?
They are carbon-based natural energy sources like coal, oil, and natural gas, formed from the remains of plants and organisms that lived millions of years ago.
What do we use them for?
We burn fossil fuels to produce electricity, heat our homes, power cars, planes, and factories, and make products like plastics.
Why is burning them so bad?
Burning fossil fuels releases carbon dioxide (a greenhouse gas) into the atmosphere.
Click here
to watch a video about how fossil fuels are formed
Our carbon emissions timeline
How much is 35 billion tonnes of CO2?
If you pumped Croke Park full of CO2, it could hold 891 tonnes of CO2 gas.
That means you can fill Croke Park
40 million times with the CO2 that we release globally in one year!
Did you know? If you kept pumping in CO2 even after the gas filled the stadium, it would change phases from a gas to a liquid. In this scenario, Croke Park can hold 495 000 tonnes of liquid CO2 since liquids are more dense than gas.
Link between CO2 and warming
Effects of climate change
Click here
to watch a video about the effects if climate change
How do scientists predict future climates?
Scientists use climate models to predict future climates.
Climate models = Computer programs that uses what we already understand about weather and climate to calculate past, present and future climates using mathematics.
There are so many different things to consider—like clouds, oceans, winds, greenhouse gases, typography, and pressure—that we need supercomputers to do all the calculations!
The accuracy of climate models is tested by seeing if they can accurately predict known past climates (hindcasting).
Click here
to watch a video about climate models.
There is hope!
What is Climate Resilience?
‘Being able to prepare for, withstand and bounce back from climate change related issues, such as sea level rise, increases in extreme weather and energy insecurity.’
Climate Resilience is a very exciting opportunity to create equitable, healthy societies and develop smarter, sustainable industries. There is a lot to gain from creating towns, cities and communities that are Climate Resilient!
Building Climate Resilience
When we talk about Climate Resilience, we also talk about Adaptation and Mitigation.
Mitigation means reducing our greenhouse gas emissions to prevent further warming.
Adaptation means changing our systems and behaviour to protect ourselves from the impacts of climate change already occurring.
We need to do both.
In many cases, mitigation and adaptation actions are linked, such as restoring ecosystems.
The Paris Agreement
In 2015 world leaders committed to addressing climate change by lowering greenhouse gas emissions.
The Paris Agreement:
Click here
to watch a video about the Paris Agreement.
Public support for climate action is stronger than ever!
In 2024, A global study with over 70 000 people from 77 countries found that:
Source: United Nations Development Programme (UNDP). Peoples’ Climate Vote 2024
We are coming up with innovative technological solutions
Source: SolarisFloat
Floating solar panels that move with the sun. It does not take up valuable space on land and is 40% more efficient than stationary farms.
Floating solar panels
AI as an early warning system
AI can be used to predict and detect extreme weather early on and can help limit the damage.
Protecting ice sheets
One company is thickening sea ice sheets by pumping water over it in the early winter to freeze, and then creating a protective layer of snow over it, so that it can survive the summer.
Source: Real Ice
Advances in electric vehicles
Electric vehicles continue to become cheaper and more convenient.
What can you do?
Our actions can make a difference, but the biggest difference will come from demanding change or action from governments & major corporations.
Here are some examples of things that you can do to make the planet healthier and fight climate change. You don’t have to do all of this. Start with what is easy and convenient. Small changes matter.
THANK YOU!
087 644 6676
globe@eeu.antaisce.org
Toshka van Eyk
Deputy Country Coordinator
GLOBE Ireland
Click the page to see how climate has changed over time
Renewable energy is safer & cleaner than fossil fuels
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