Severely Intense Climate Conditions
Let's dive into the wild world of weather, shall we? Every day, we chat about the skies above, whether it’s affecting our work, play, or travel. But when those meteorologists start spouting off about severe weather events, we sit up and take notice.
Weather vs. Climate: What's the Difference?
You've probably heard the terms 'weather' and 'climate' thrown around interchangeably, but trust us—they're not the same thing. Oh, no. Weather is all about the short-term state of factors like temperature, precipitation, and wind speed in a specific area. Climate, on the other hand, is the average weather conditions over 30 years or more. Weather changes every day, while changes in climate happen gradually. As the saying goes, "Climate is what you expect, weather is what you get."
New Zealand's Weather Bombs
New Zealand isn't immune to extreme weather events. While not technically correct, the media loves to call short, intense storms that bring gale force winds and heavy, horizontal rain 'weather bombs.' The more accurate term? 'Bomb cyclone.' This is when the air pressure drops 24 hPa (hectopascal pressure unit) in just 24 hours. Bomb cyclones can cause some serious disruptions—strong winds can wreak havoc on transport, damage property, and knock out power lines. Heavy rains might trigger flooding and landslides. But a real weather bomb in meteorological terms is something else entirely, like Cyclone Bola.
New Zealand's Annual Rainfall
Topography plays a big role in regional rainfall in New Zealand. Those mountains trap moisture from the westerly airstream, and since the country sits in the Roaring Forties—a belt of westerly wind that winds its way around the lower part of the southern hemisphere—winds are just blowing in from all directions. Add Cook Strait between the North and South Islands, which enhances wind speed and strength, and the South Island's west coast and the Rimutaka Range end up drenched with more than 6 meters of rain a year!
Extreme Weather Events in Australia
Australia's been buffeted by some tough weather lately. In 2013, the country experienced its hottest heatwave ever, with over 70% of the continent sizzling above 42°C at the beginning of the year. The national average temp on January 7, 2013, was 40.3°C. Australia's known for its heatwaves, but this event was particularly notable because the extremely high temps were so widespread and persisted for two weeks straight. In 2014, 2015, 2017, and in January 2019, Adelaide hit its all-time high temp record—46.6°C. Over 90% of Australia sweltered in extreme heat in 2019, making it the hottest year on record. A heatwave occurs when the daily max temp exceeds the average daily max by five degrees or more for five straight days.
Tropical Cyclone Yasi
Tropical Cyclone Yasi, the biggest cyclone to ever hit Australia, struck in 2011. This storm absorbed energy from the warmer-than-normal waters off the northeastern coast of Australia and expanded to 800 km in diameter (that's more than double the size of normal Pacific storms). Unfortunately, Yasi moved quickly and missed many of Queensland's larger towns, but it still managed to dump up to 200 mm of rain in just two hours on Melbourne and regional Victoria, causing major flooding.
Changing Weather and Climate
We all know the weather can be unpredictable, and fortunately, meteorologists are kind enough to track weather systems and warn us about severe events. But the big question is this: How is climate change impacting weather in New Zealand, Australia, and other parts of the world?
New Zealand's Ministry for the Environment predicts an increase in extreme weather events such as droughts in the east, increased flooding due to more frequent and intense winter rainfalls, and coastal areas at risk due to rising sea levels. Land-use management can help reduce the impacts of these extreme events.
Bridge Damage from Cyclone Gabrielle
In early 2023, major parts of New Zealand were hit by severe weather events. The Auckland Anniversary Weekend flooding saw an entire summer's worth of rain fall in a single day. Just days later, Severe Tropical Cyclone Gabrielle caused even more destruction. The New Zealand MetService reported, "Between the 12th and 14th of February, parts of Aotearoa New Zealand recorded rainfall amounts of 300-400 mm, wind gusts of 130-140 km/h, and waves up to 11 meters high along the coast."
The relationship between extreme weather events and climate change is complex and multifaceted—both countries are experiencing an increase in severe weather phenomena linked to broader climate trends. Enhanced preparedness and adaptation strategies are essential to mitigate future climate-related disasters.
Science and environmental science have a crucial role in examining the impact of climate-change on weather patterns. For instance, the increase in extreme weather events such as the heavy rainfalls in New Zealand, due to more frequent and intense winter rainfalls, can be linked to climate change. This is part of the broader trend observed in Australia, where the frequency of heatwaves and the size of cyclones like Tropical Cyclone Yasi have noticeably increased. Hence, it's essential to understand weather patterns not just for daily forecasts, but also to predict and prepare for extreme weather events that may be connected to climate change.
