We cannot say that climate change was entirely responsible for the Black Summer Bushfires of 2019/20, but we can certainly say that it played a very important role.

2019 was Australia’s hottest and driest year on record. The combination of hot and dry weather leads to high fire risk because it produces fuel (plant material) that is exceptionally dry and easy to ignite, and it also produces extreme fire weather (hot, windy) that makes it difficult to fight the fires.

These extreme climatic conditions in 2019/20 were strongly influenced by climate change. However, the fires were also influenced by climate events that occur naturally from time to time. An example of this is that the fires occurred during an El Nino event, which is a natural climate pattern that leads to hotter and dryer weather in Australia. The effects of climate change, like hotter weather, made the natural El Nino event much more extreme.

To summarise, the Black Summer Bushfires occurred during the hottest and driest year on record in Australia, which is largely caused by climate change. Even though there were other naturally occurring cyclical climate events involved (like El Nino), the fires would have been more manageable without human-caused climate change.  

When organic waste decomposes, carbon dioxide and methane gas is created. Methane is created when there is no air present, while carbon dioxide is the natural product when anything rots in air. So, basically – methane is produced when food goes to landfill, and carbon dioxide is produced when food is composted. As you probably know, carbon dioxide and methane are both greenhouse gases that are responsible for climate change. But methane is more than 25 times as potent as carbon dioxide at trapping heat in the atmosphere. So composting is better than sending food waste to the tip, but a better solution is for us to minimise food waste wherever we can.

The production and disposal of other types of waste also produces greenhouse gases, because these processes use natural resources such as water and fuel. Plastic waste produces greenhouse gas emissions during every stage of its lifecycle. The production and transport of plastic is dependent on oil, gas, and coal and so releases carbon dioxide into the atmosphere. In fact, waste management in general – including transportation, incineration, and other processing – is a huge contributor to greenhouse gas emissions. 

Microplastics are described as any plastic that is less than 5mm in size. Interestingly there are two types of microplastics, primary and secondary.

Primary microplastics are plastic items that are manufactured to be very small. For example, microbeads are tiny balls of plastic that can be found in personal hygiene products such as face scrubs, soaps, and toothpaste. Microfibers are tiny strands of plastic that are used to make clothing such as polar fleece jumpers.

Secondary microplastics are a result of larger plastic items breaking down into smaller and smaller pieces. For example, a plastic bottle breaking down into smaller fragments of plastic or a Styrofoam box breaking into smaller pieces. The breakdown of large plastic items into microplastics are caused by weather weakening the material, and other objects scraping and breaking the larger plastic objects.

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.