Climate change affects the earth in many and complex ways. Much research attention is currently being directed towards the influence of climate change on biodiversity both on land and in the oceans.

You’ve likely seen discussion about coral bleaching on our own Great Barrier Reef. Research from the IPCC (Intergovernmental Panel on Climate Change) shows that with global temperature rise of 1.5°C, 70-90% of coral reefs will be lost. With a rise of 2°C, 99% percent will be lost. Along with coral loss will come the degradation or loss of whole reef ecosystems and the species evolved to live in them.

The oceans have absorbed around a third to a half of carbon dioxide released into the atmosphere through human activity since the 1850s. This process is changing the pH of ocean water, making it more acidic. Research shows that there has been a 26% increase in ocean acidity since the 1850s – which is about 10 times faster than at any time in the last 55 million years. Ocean acidification makes carbonate less available in sea water and as this is the building block of the shells and skeletons of many marine organisms, it has negative consequences for many marine organisms. Molluscs and some species of plankton are particularly affected. Ocean acidification also further weakens coral, making it more vulnerable to destruction in storms. Some species may benefit: some algae and sea grasses may increase their growth rates. This image summarises how some key marine organisms will likely be impacted:

On land, climate change impacts on ecosystems are already widespread. One of the most visible may be the loss of millions of hectares of pine forest in British Colombia in Canada since the 1990s. This widespread damage has been caused by an insect called the Mountain pine beetle (Dendroctonous ponderosae). Normally kept in check by cold winter temperatures, the beetle has been able to survive winters that have recently become warmer due to climate change and has killed trees across vast areas.

In other places, species that are adapted to cool alpine or temperate environments move up towards mountaintops as temperatures warm – however, when they reach mountain summits, there is nowhere else for them to go. One example of this is the White lemuroid ringtail possum (Hemibelideus lemuroides) which lives only in the high altitude Daintree cloud forests here in Australia and is now only found on a few isolated mountain tops. It’s unable to survive temperatures above 30°C for very long.

Of course, animals that rely on ice, for example, Polar bears and Ringed seals in the Arctic, and Emperor penguins in the Antarctic, will be increasingly threatened as ice melts. A recent study has warned that almost all Emperor penguins in Antarctica will die out if no changes are made to greenhouse gas emissions.

The situation for the planet’s biodiversity is certainly very precarious and confronting – however, these losses are not inevitable. Science tells us that if we can work globally to limit greenhouse gas emissions quickly and dramatically, we would see a stabilisation of temperatures within 20-30 years. Restoring natural habitats has been identified as one way to both protect biodiversity and store carbon – a win-win for local biodiversity and the planet as a whole. Reducing emissions and restoring habitats (sometimes called “rewilding”) are essential now to protect the remarkable biodiversity of planet Earth.  

This is an excellent question, and one of the questions most students want an answer to. You can be someone who takes climate action!

Each of us can act individually (on our own) and collectively (together with others) to act on climate. We know, from scientific evidence, that climate change cannot be stopped and is happening already – but it can be reduced and slowed down. People today and into the future (including you) can make changes and decisions that will greatly reduce climate change and its impacts.

Some of these decisions are happening on a systemic scale - they the really big changes we need to reduce emissions from industries and electricity generation.

For example, world leaders are meeting together at COP26 (which is the UN Climate Change Conference of the Parties) to discuss pathways to do this – in particular, to ensure that global temperature rises do not exceed 1.5 degrees, and how we can adapt to climate change impacts into the future. If we can manage to greatly reduce global greenhouse gas emissions (such as carbon dioxide) we can limit climate change. 

You might wonder how young people can influence big changes like this? By using your voices! Young people are involved in many groups and movements such as the School Strikes for Climate that have already made a difference to the way world leaders think about climate action.

At a smaller scale, all of us can do something to make positive changes and have an impact on tackling climate change. Some people can do more and less than others, and that is OK - it’s great actually because lots of small changes can lead to big impact. In everyday life, there’s lot that you might be able to do, for example: 

• You can aim to take the bus or walk, or ride your bike to school more. 
• You could eat more vegetables, and eat meat less often (maybe even encourage your family and friends to have ‘meat free Mondays’?!). Plant-based foods generally produce fewer greenhouse gas emissions and they also require less energy, land, and water usage. 
• You can speak up! Tell your friends and family about climate change and the small changes each of us can do to make a difference - remembering that we all have different abilities to make these changes, big and small. 

There are a lot more ideas you can check out on our 'What can I do?' page.

The sooner we can reach net zero emissions the better it will be. Net zero means that the amount of greenhouse gases going into the atmosphere are no greater than the amount being absorbed out of the atmosphere. 

The term 'net zero' is important because it means we will no longer be contributing to increased global warming.

We have already seen a global temperature rise of over 1°C and we are experiencing the consequences of that increase already. The terrible bushfires of 2019-2020 and the three years of back to back coral bleaching on the Great Barrier Reef show us that our climate system is highly sensitive to even small changes in temperature. So, we cannot be sure that achieving net zero by 2050 will avoid exceeding the 2°C limit and 1.5°C target that we set ourselves in the Paris Agreement or that limiting warming to 1.5°C or 2°C will avoid serious harm.

The longer we wait, the higher the chance of failure. Most scenarios associated with the 2050 target only offer a 50 or 66 per cent chance of staying below the temperature limit. That isn’t very reassuring, and we should be doing all we can to increase our chances of success by bringing forward our decarbonisation commitments. Earlier action to arrest and reverse emissions trajectories will be much better than waiting until the last minute and possibly having a situation where temperatures overshoot the 2°C limit.

Finally, making the transition now will save us money in the long term. New energy and business opportunities will open up if we embrace decarbonisation now and we can avoid some (but not all) of the droughts, bushfires and heatwaves that cause so much economic loss, environmental damage and human suffering.