Does Cyclone Gabrielle have you thinking about climate change? You're not the only one

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Does Cyclone Gabrielle have you thinking about climate change? You're not the only one

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If the reality of the climate crisis hadnt sunk in for you until this summer, youre probably not alone. Humans simply arent wired to assess future threats - particularly ones they cant see, like a warming planet. But with yet another cyclone hitting the North Island - as fears of drought escalate in parts of the South Island - the impact climate change will have on our lives is becoming harder to ignore. To get you up to speed, heres a quick guide to the basics, with some tips for taking action at the end. Climate change doesnt cause cyclones but it does make them more intense . Tropical cyclones get their energy from the sea surface, and the warmer the water, the more energy they have to work with. This makes for more powerful storms that grow faster. Sea surface temperatures in New Zealand have been recording record levels this summer. Equally, the warming atmosphere also helps to fuel storms. Hot air holds more moisture , causing heavier rainfall, like the recent downpours in Auckland that led to widespread flooding. Researchers found climate change was likely responsible for 10 to 20% of that rain. The infamous greenhouse gases. These gases - mainly carbon dioxide, methane and nitrous oxide - have accumulated in the atmosphere where they trap the suns heat reflecting off the earth. Professor James Renwick, a climate scientist at Victoria University Wellington, says this process is akin to having a blanket on a bed: "A thicker blanket, a warmer body; a thicker blanket over the earth, a warmer earth." Mainly from human activities , namely burning fossil fuels, agriculture, and cutting down trees. We burn fossil fuels like coal, oil and gas to fuel cars, trucks, planes and trains and to heat our homes and workplaces. This releases carbon dioxide into the atmosphere. Equally, agriculture produces methane, the gas released when cows and sheep belch. Nitrous oxide is released by fertilized soil and animal waste. Deforestation has a dual impact - trees absorb and store carbon dioxide which means they can take some of the carbon out of the atmosphere; but when they are cut down and burned, this carbon dioxide is released. Since the beginning of the Industrial Revolution, people have burned more and more fossil fuels and changed vast areas of land from forests to farmland, ramping up the amount of gas in the atmosphere. No. Carbon dioxide is the biggest contributor to climate change and can stay in the atmosphere for thousands of years. Nitrous oxide can stay in the atmosphere for about 120 years. Methane has a more intense but shorter-term warming effect. The good news is if methane emissions were reduced rapidly the warming caused by past emissions would naturally decrease within a few decades. Human-produced greenhouse emissions have already heated the planet by an average of roughly 1.2 degrees Celsius, compared to the pre-industrial world. At 1.5C, the oceans will rise faster, extreme weather such as droughts and heatwaves will become more frequent, and crops, plants and animals will shift to different locations (with the pressure pushing some to extinction). Scientists have warned that warming above 1.5C leaves Earth vulnerable to climate tipping points, causing more severe economic and public health impacts everywhere, and makes life in some Pacific nations untenable . Its agreed that so far, the world hasnt done enough to make 1.5C a reality. Its much more likely that, by the end of the century, global temperatures will be 2.8C above pre-industrial levels. New Zealand is in the top 10 countries per head of population for emissions. We rank similar to the US and Australia and ahead of China, with the annual emissions footprint of the average Kiwi being 17 tonnes, the sixth highest among OECD countries. And while other nations are managing to slow the amount of greenhouse gases theyre pumping into the atmosphere, New Zealands gross emissions have increased 26% since 1990 . In 2015, 196 countries signed the Paris Agreement, an international treaty on climate change. Its goal is to keep the rise in global temperature to well below 2 C above pre-industrial levels, and preferably limit the increase to 1.5 C. But since then, the world particularly the wealthiest and developed nations has failed to take meaningful action on emissions. New Zealand is among those struggling. While we have a new law - the Zero Carbon Act - which outlines our climate targets, and our commitment to reduce our emissions (except methane) to net zero by 2050, analysis has found we are not on track to do so. New Zealands biggest problems are agriculture, energy, and transport. Half our emissions come from agriculture, and 40 percent from energy. Transport makes up the bulk of the energy emissions. Yes, there is still time left to limit warming. Ideally, we would stay inside 1.5 , which would halve the amount of land lost to the ocean, reduce the number of people exposed to natural disasters and allow some species to hold on. To do so, carbon emissions need to fall about by 43 per cent from their pre-pandemic levels by 2030 and 84 per cent by 2050. At the moment, that seems unlikely , but with drastic action it is technically still possible. James Renwick, the climate scientist, says the best thing we can do as individuals is hold the government to account. "Make sure you let your MP know you want to see this happen and make sure your family and workmates know that climate change is a big deal, he says. But making changes at an individual level is important too. "Use less energy, make sure your house is insulated, take the bus instead of the car - those sorts of obvious things. If it's a nationwide effort then it does make a difference. To start with, you can calculate your carbon footprint here , and read tips for a lower carbon lifestyle here . Theres a guide for businesses here . Stuff also has a climate newsletter, and a section on its website devoted to climate news. Climate lingo can be confusing - theres a helpful guide to terms like net zero and carbon sequestration here . Even if we stopped emitting greenhouse gases right now, its going to take a long time to remove all the human-made greenhouses gases from the atmosphere . Its more likely that our immediate future holds the risk of an increase in extreme rain, drought and wildfires. Areas that rely on rainwater for drinking and pasture will be especially hard-hit by droughts. Rising sea levels will make many coastal communities and infrastructure vulnerable to floods, tsunamis and other natural disasters. Climate change will affect all aspects of our lives - the loss of taonga species and native ecosystems, our physical and mental health, how we spend our leisure time, the economy, buildings, infrastructure, our industries. Our best hope is to start with limiting further warming to that crucial 1.5 degrees Celsius.