Wednesday, February 7, 2018

Embrace the Cloudy Skies

We all have those days. You wake up to the light pitter-patter of raindrops on the roof. Peering tentatively out the window, and all you see is a blanket of gray. You pull the covers back over your head and hope no one notices you straggling in several hours late for work. 

Last week, many of my Brisbane compatriots may have tried to pull off something along these lines, bemoaning the gray and rainy weather. Though I love the usually brilliant blue skies and sunny days of Brisneyland, I have to admit that my Seattle upbringing makes me crave dreariness and gloom (weather-wise) every now-and-again. But the lack of rain piques my interest (and concern) for another reason. It's indicative of a worrisome trend across the globe - one that is not just about how much water falls to the ground in a specific place, but at what time of year and how intensely. So, let's talk a bit about rain!

Queensland is home to the Great Barrier Reef and a belt of tropical rainforest. But it also seems to have a recurrent precipitation problem. During December, arguably the start of the wet season, rainfall and soil moisture were below average for most of the state. Here in Brisbane, like the rest of Southeast Queensland, we rely on capturing rainwater in reservoirs throughout the year to feed demands for drinking water, etc. While this is efficient during the frequent summer deluges, it leaves us at a bit of a risk when the skies are clear for too long.

Moving to a more arid region, Cape Town has made headlines repeatedly in the last week or two. This is because the South African city with a population of 4 million people is likely to run out of this year's water by around May. Growing water demand (i.e. more people) and record-level drought (potentially augmented by climate change) are being implicated in the urban water shortage. Ultimately, the city is drawing on its underground aquifers and rivers faster than rain can replenish. Indonesia's capitol city, Jakarta, also made headlines for unsustainable use of groundwater (caused by illegal well-digging), though the big concern here is the risk of land sinking and falling below sea level.

Our last case study of rain troubles is Seattle, WA. This is another story altogether. Here it rains. In fact, in 2017, Seattle got a year's worth of rain in just 5.5 months. Cool, so water shouldn't be an issue, right? Climate change predictions show Pacific Northwest of North America as getting wetter and warmer. Unlike arid Cape Town or sub-tropical Brisbane, much of Seattle's drinking water comes from spring snowmelt. And this, my friends, is reliant on the temperatures dropping low enough for winter snows to fall and remain in the upper parts of the watersheds. Or, if precipitation becomes more concentrated at certain times of year, when it is less likely to fall as snow, we are also likely to see water shortages.

So Brisbane is back to sunny skies, but rain should never be far from our minds. We had three different water supply stories, but a common thread of precarious precipitation ran throughout. It matters where, when, and how much, but perhaps we could still embrace those cloudy days just a bit more!

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