If all the ice at the poles melted, the sea level would rise by nearly 70m. Because there is so much ice, it takes a very long time to melt it all. But it is currently melting, causing the sea level to go up by about 2 mm every year. At the current rate, we will all be long dead from old age before they are fully melted. But what happens to our children and the world they live in?

As the sea level goes up, some coastal cities and towns will start to flood and the higher sea level will erode the land from underneath the buildings. There will be difficult choices in the future; we will need to decide what gets left behind as we move to higher ground and what we try to save.

This is a really important question – with an “it depends” kind of answer. What we know for sure is that climate change is already, and will continue to, have really big impacts. The sorts of impacts that climate scientists expect that future generations will face include more extreme weather events, sea level rise, biodiversity loss, environmental degradation – all of which have complex and interrelated flow on effects. It is also important to remember climate change is not just a problem that is going to have impacts in the future. It is already having significant impacts to people’s lives right now!

What’s tricky about this question is that the kinds of impacts and extent of those impacts that future generations will experience however, depends on different mitigation scenarios. What that means is that if action is taken now to reduce greenhouse gas emissions and reach net zero CO2 emissions, then the scenarios for future generations will be less severe and dangerous then if action takes longer or doesn’t happen at all. What is also tricky about this question is that projections of what the future may look like depending on current actions could be much more severe and extreme if we reach ‘tipping points’ (some of the other experts have answered questions about these).

One of the really helpful things about these climate models and scenarios is that they show us really clearly what we need to do now to ensure a safer world for future generations. We can be a part of creating a more just and safe world for future generations by taking action now.

You could also read these articles about climate projections for 2500, and what the earth will be like 500 years from now.

In Tasmania, invasive long-spined sea urchins, Centrostephanus rodgersii, have caused significant ecological issues in local marine ecosystems, made worse by climate change.

The sea urchins have multiplied rapidly due to a combination of factors linked to climate change. Warmer ocean temperatures have facilitated the range expansion and reproduction of these urchins. Additionally, disruptions in local ecosystems, such as overfishing of their natural predators, have led to their unchecked population growth.

Their increase in numbers and range expansion have resulted in the degradation of vital marine habitats, particularly adding to the destruction of giant kelp forests. The sea urchins graze voraciously on kelp, leading to 'urchin barrens'—areas where kelp forests have been decimated, leaving barren areas that lack biodiversity and ecological richness.

Climate change has contributed to the conditions favouring the increase of these sea urchins, exacerbating their impact on Tasmania's marine ecosystems. The combination of warmer waters, reduced predator pressure, and altered ecological balance has created an environment that allows the sea urchins to thrive, leading to significant ecological disruption around the state.

This is a well-timed question, because Australia is doing more than ever before to mitigate, or slow, and eventually stop climate change. This year, at the Australian Federal election in May, Australians elected a clear majority of candidates who support more ambitious climate action – yay! So far, the new government has introduced the Climate Change Bill 2022 which is Australia’s commitment to reduce greenhouse gas emissions by 43% (below 2005 levels) by 2030, and achieve net zero by 2050.  This is a good step in the right direction, but it could be more ambitious, with greater emissions reductions and higher renewable energy targets. To achieve the target it is critical that the government review the rules that define how much Australia’s largest greenhouse gas emitters can emit, known as The Safeguard Mechanism. The reform is underway and the government aims to release the new rules in July next year.  

Key considerations for the review are the setting of limits for emissions, managing any disadvantages that businesses may face in the global market and ensuring that a reduction of emissions in Australia doesn’t lead to an increase overseas, and introducing a carbon credit system. Many members of parliament have criticised the proposal to include a carbon credit system, because previously carbon credit systems have failed to reduce emissions. So, the scheme is currently under review.  

The new government has also recently made a commitment to increase protected areas in Australia from the current 22 percent to 30 percent by 2030. This has a dual aim to protect habitat for threatened species and contribute to emissions reduction. Every action that prevents carbon from entering the atmosphere will help to mitigate climate change. 

A protected Tasmanian saltmarsh. Source: Australian Mangrove and Saltmarsh Network Conference. 

In addition to electing a government that supports climate action, the people of Australia have also been doing lots of things to reduce the amount of carbon that enters the atmosphere and mitigate climate change. Where possible, people are consuming less, recycling more, eating more sustainable meats and more delicious vegetables, sometimes even growing some of their own food, replacing their cars with electric vehicles, driving and flying less, using sustainable transport, not supporting banks that invest in fossil fuel-based industries, supporting renewable energy initiatives and making buildings more energy efficient…overall, Australians are engaging in climate action.  

Australians are coming together as a community to demand more ambitious climate action, greater emissions reductions and stronger accountability from our leaders. Many community groups, land managers and land management organisations are working with Traditional Owners and First Nations people to incorporate indigenous knowledge to restore and care for country. Researchers from a diverse range of fields are coming together to share knowledge in how we can more effectively mitigate climate change. Australians are connecting with natural environments and advocating for the protection of places that store carbon, like forests, saltmarshes and oceans. Climate action is gaining momentum!  

I have been asked a lot about how climate change works – what is it, how does it happen, and what happens to the Earth with global warming. To answer this I’ll start by talking about the difference between weather and climate. As I’m sure you know, weather is the changes in temperature, rainfall and wind that we see outside from day to day, while climate refers the usual weather of a place. Tasmania has a cool temperate climate overall, but the west coast has a wetter climate than the east coast, and the central regions have a cooler climate than the coast. The Earth also has a climate; Earth’s climate is what you get when you combine all the climates from around the world together. 

Climate change is a change in the usual weather of a place. While the weather can change in just a few hours (as it often does in Tassie!), climate change occurs over many years. And in fact the Earth’s climate has always been changing. As I’m sure you know, there have been times in the past when the Earth was much hotter than it is today, and also times when it has been much cooler. But an important difference with climate change caused by human activities is that the change is occurring much, much faster than we have ever seen before. 

There are lots of different things that can cause climate to change – volcanic eruptions, changes in the world’s oceans, and changes in the activity of our sun. Climate change caused by humans is due to the gases we release into the atmosphere – particularly carbon dioxide from burning fossil fuels, but also methane and other gases. These gases cause a green-house effect which traps more of the sun’s energy in Earth’s atmosphere and so warms the planet. This warming also causes changes in other features of our climate such as rainfall. 

Earth's temperature will keep going up for at least the next 100 years. This will cause more snow and ice to melt and sea levels to rise. Some places will get more rain and others will get less rain. There will be more heatwaves and some places might have stronger storms. The sooner we can stop emitting greenhouse gases and implement solutions to take excess carbon dioxide out of the atmosphere, the better chance we have of minimising the impacts of climate change on our Earth. 

In most places, energy generation, using fossil fuels, is the largest contributor to climate change. In contrast, Tasmania is lucky to have a low-emissions energy generation – much of our energy is produced by hydroelectricity. The single biggest emitter of greenhouse gases in Tasmania is the agriculture sector – which contributes 34% of our overall greenhouse gas emissions. However, carbon accounting (the process of calculating overall emissions and offsets) is quite complex in Tasmania. Let’s take a look…

In fact, Tasmania is one of the few places in the world to have already achieved “net-zero” status. That means, Tasmania currently takes more carbon from the atmosphere than it emits - absorbing and storing carbon in our forests and our soils. Tasmania’s greenhouse gas emissions in 2020 were -3733 kilotonnes CO₂ – e:  “CO₂ – e” means “carbon dioxide equivalent”. This is a measure used to compare the emissions from various greenhouse gases based on their global warming potential.

Tasmania’s negative emissions profile is a nationally and internationally significant achievement, but there is more to the story. If we want to keep this status, we can’t be complacent. Currently, Tasmania’s main emissions come from agriculture (34%), industrial processes (19%), transport (21%), non-hydro energy generation (21%) and waste (5%). Tasmania’s main “offsets” – or sources of carbon absorption – are forests and soils: a sector known in carbon accounting as “land use, land use change and forestry” or “LULUCF”. So Tasmania’s emissions profile looks like this:

Keeping our emissions profile low over the longer term will mean we need to do better at cutting our overall (or “gross”) emissions – on the left, above. In fact, we haven’t reduced these emissions much for 30 years, and emissions from agriculture have increased the most over the last decade. Importantly, research shows us that the effects of climate change – like rising temperatures, bushfires, and changing rainfall patterns – will decrease Tasmanian forests’ capacity to absorb carbon. Also, continued old-growth forest clearing and the maturing of managed forests means that over time, our forests be less of a carbon sink. If Tasmania keeps a business-as-usual approach, emissions will remain below net-zero until about 2025, but, from 2030 onwards particularly in years with major bushfires, Tasmania will likely become an emitter of carbon once again.

We therefore need to work to reduce gross emissions, and better protect our original forests to keep our net-zero status long term.

Thanks for asking this important question. In order to solve a problem, first, we must identify and define the problem. 

Even though the science of global warming was discovered as far back as 1856, climate scientists only started to use the term ‘global warming’ in the 1980s. Global warming refers to the average global surface temperate increase caused by human emissions of greenhouse gases. Global warming is mainly understood as temperature rise, but it’s a bit more complicated than this.  The warming leads to changes in weather patterns and air and water currents, which can mean that in a few places, colder weather is sometimes caused by global warming. The term confused some people, so scientists started to use a different term, ‘climate change’. 

Climate change refers to the long-term change in the Earth’s climate.  It is a more comprehensive term because it includes side effects of warming such as melting glaciers, heavier rain and storms, more frequent drought, frequent bushfires, changes in ocean circulations and ocean acidity. So climate change describes how weather patterns will be affected differently around the globe. 

If you’d like to keep up with the latest news in climate science, scientists have started to use new terms:

Climate disruption, climate crisis and climate emergency are a few of these. The common feature of these terms is that the rising average global temperature has consequences (for example disruption) and requires urgent action.  These terms may be more effective to get the message out because climate change action is urgent. 

Under the most extreme climate change scenarios sea levels could rise by as much as 4-6 m by 2100. When sea level rises by, let say 5 m, that means anything less than 5 m above sea level at the moment will be underwater. The first place to become completely submerged will be the country with the lowest maximum elevation above sea level. That happens to be the Maldives, which has maximum elevation of only 1.8 m! That could be submerged by even low to intermediate climate scenarios.

Luckily for Tasmania, it has lots of mountains, meaning most of the state well above sea level. The high point in Tasmania (mt. Ossa) is 1,617 m above sea level. Even the most extreme sea level rise projection don’t come close to reaching that, so there is a near 0% chance Tasmania becomes completely submerged. Although towns, homes, and ecosystems on the coast, near the beach, could definitely run into trouble!

This is a very important question, thanks for raising this at a time when urgent action is needed by all countries. Human activity is the main cause of climate change. Burning fossil fuels is the main activity that causes climate change, and changing land from forests to agriculture has also significantly increased the concentration of greenhouse gases in Earth’s atmosphere, leading to climate change. 

To find out which country is the biggest polluter, we will look first at where the fossil fuels that create Carbon dioxide (CO₂) pollution are coming from.

This map changes the area of each country to show how much fossil fuels it produces. The biggest producer of fossil fuels is the United States of America. Australia is also in the top 10 fossil fuel producing nations, at number 8. Many countries sell a lot of their fuel to other countries, as well as consuming it themselves. The fossil fuel industry is only made possible because people are buying and using these fuels, so we also need to ask who uses the most fossil fuels.

Climate scientists measure the level of carbon dioxide (CO₂)  emitted by a country and divide it by the population of that particular country.  The result gives us carbon emission per person. This is a fair way to see which countries use most fossil fuels. Based on the recent United Nation’s Intergovernmental Panel on Climate Change (IPCC) report, the most polluting country per person (per capita) is Qatar (located in the Middle East). The reason for this is that Qatar is a major producer of natural gas, oil and oil products, and sells these to countries across the world. Other neighbouring countries, Saudi Arabia and Oman are also among the biggest polluters.

Wow, that really is the million-dollar question, but an important one to ask! I think the most effective strategy is being engaged in whatever way you can. Climate change is a human made problem - the solutions to climate change will also have to come from us. So having passionate, curious, enthusiastic and dedicated people engaging in the process, for me, is the most effective strategy.

How you engage in this can be completely up to you! You don’t have to be a mathematician modelling carbon emissions, or an ecologist investigating the impacts of climate change on the Great Barrier Reef 😊 You can have a conversation with your friends and family about climate change and tell them why it is such a big issue and what they, you, and we all can do to take action and make a difference. You can discuss your worries for the future and the changes you would like to see. You can take part in protests about political decisions you disagree with. You can sign and share climate action petitions online. The most important thing is to make your voice heard.

There are lots of things, big and small, we can all do to help address climate change. The important thing to remember is that we should try to do something but not feel guilty if we can’t do everything. We all have different abilities 😊 Check out the Curious Climate Schools website for ideas on ways we can take action on climate.