local weather report



The weather matters in particular ways to gardeners. If you're a gardener, you need to know what plants are likely to thrive in the particular weather conditions you're expecting. When I started this blog, the weather had been so hot and dry for so long that I was contemplating planting lots of succulents to withstand the challenging conditions. If I had done so, by now they would have rotted away in the moisture resulting from two years of steady rain.


So weather matters. And as it happens, in Australia there is the opportunity to obtain precise and accurate measurements about changes in the nation's temperature and rainfall over a 100 year period.

The Bureau of Meteorology started measuring Australia's weather 100 years ago. There are nearly 800 weather stations across Australia. Over 500 stations are fully automated. 112 stations have information going far enough back and accurate enough to be counted as part of the 100 year record.  The data collected is fed by cables to central stations at the national bureau headquarters in Melbourne. The data is digested, and becomes a record of the history of Australia's weather.

Some figures...

In 60 years, we've lost a third of our total snow cover.


On average, Australia's temperature has gone up 0.9 of a degree.

Sea temperatures around Australia have risen by 1 degree on average, but around Tasmania it has risen an amazing 2.28 degrees, about 4 times the global ocean average. Scientists are not sure why this is so.  

Sea levels have risen everywhere. We've got 9 times the number of flooding events for structures at sea level than we had 100 years ago.

'Every parcel of air, every ocean current, every weather system is now about a degree warmer. And when you go through and do the physics, that's actually a hell of a lot of energy added to the climate system in general.' (Dr Karl Braganza, Australian Bureau of Meteorology)

And that added energy means extreme weather events occurring more frequently and more extremely.


Life cycle and growth patterns of flora and fauna change, as they adapt (or not) to the rising temperatures. For example, butterflies are very temperature-sensitive. Melbourne's common brown butterfly emerges from its chrysalis nearly 2 weeks earlier than in 1940.


Extreme heat days become more common. In 2009 Melbourne's temperature spiked, breaking the Victorian record by 1.6 degrees. The temperature hit 46.5 degrees! The heat led to fires known as 'Black Saturday' in which 173 people died.  And they weren't the only casualties. 370 more people died that week from heat stress.


Wildlife suffer when it is very hot.  In 2010 in southern Western Australia a flock of endangered black cockatoos died when the temperature reached 48 degrees.

photo from WAtoday.com.au

 Because of the rising temperature of the sea, many New South Wales fish have moved south to Tasmania.

 Last year, in southern Western Australia, the sea got so hot, it killed a coral reef, leaving it covered in algae. Whale sharks, normally living in northern waters, were seen in the south, outrunning the hot water, searching for cooler water. This was the biggest heatwave on record to hit Australian waters, and lasted for 5 months.

from Australian Marine Conservation Society website

Changes in ocean temperature affect the type of weather we get. The warmer the water, the higher the rainfall. In the last 2 years there has been more rain in Australia for a 2 year period than ever since records began. The years 2010, 2011 and 2012 saw the worst floods in the history of the state.

from website of Victorian Dept. of Sustainability and Environment
But looked at in the longer term, there has been dehydration across the south of Australia, especially in south-west Australia! The worst drought ever in Victoria started in 2001, and lasted 9 years. When it ended and it started raining, farmers rejoiced at first, until their crops were inundated by floodwaters.

This is a pretty confronting post, but I want to face reality, not deny it. The point is that global warming is not something that our children will have to worry about it in the future - it's here with us now. After 2 years of mild summers, the weather forecast for this summer in Victoria is hot and dry, with the risk of fires as great as it was for Black Saturday in 2009.

So it's more than simply choosing plants that we gardeners have to think about.  How are we going to prepare for the changes? In Alice Through the Looking Glass, the Red Queen said that it takes all the running you can do to stay in the same place. But that no longer works. Because the same place has disappeared into the past, and no matter how fast you run, you'll never get back there again.

A biblical warning against global warming, by Jean Gouders


Source: Catalyst, ABC TV, 15/11/2012




















Comments

  1. Great post!!! You know that it's the same story here in Tucson. Almost exactly the same story. Here in the US, this is a "hot" topic. Whatever the case, more people and creatures will die from this heating up around our planet.

    ReplyDelete
    Replies
    1. one consolation, I guess, is that as it gets worse, people may find it harder to ignore and continue business as usual.

      Delete
  2. So many helpful facts in this post. There's not denying weather is changing here in the U.S., too.

    ReplyDelete
    Replies
    1. hi beth, we're all in the same boat, or on the same planet ...

      Delete
  3. Thank you for this post. I completely agree that global warming needs to be confronted. Most people are in denial. Even people who accept the reality often ignore it in pursuit of short term rewards. We need many more posts like this.

    ReplyDelete
  4. I think the whole planet is involved, extremes of weather everywhere. At this very minute half of the UK is under water, railway lines washed away, landslides blocking roads and yes, it has been a lot warmer than usual for November. The Ice cap in the Arctic is melting but at the same time in the Antarctic the ice cap is increasing, I don't understand what is going on.

    ReplyDelete
    Replies
    1. I think the science is out there, it's complicated but it seems we've caused it and we don't seem to be able to change our lifestyles. What you describe is horrendous - transport services destroyed. If that happens a lot, maybe we'll be forced to change our lifestyles.

      Delete
  5. It's so sad that weather changes. It happens so fast that the Mother Nature can't follow. It's heartbreaking to see animals suffering.

    ReplyDelete
  6. Catmint, a well-researched post written in a readily comprehensible way. Thankyou.
    I, too, often feel daunted, not knowing what's going to come next. The reliability we knew many years ago has gone. I can't help but feel that we have the strength and capacity to deal with it all.
    It's a pity there are immense forces in this world whose ( conscious or unconscious ) intention is destructive. We can only love and do our best. And isn't that everything?

    ReplyDelete
    Replies
    1. I don't know about love being everything. I wish it were so. I think maybe we need to be politically active as well. But then you get caught up in a lot of hate and conflict ... I don't know ... I often feel optimistic about the future too, but sometimes I feel very pessimistic.

      Delete
  7. I do wonder what will become of our gardens, and I wonder what people in ages past did when the weather changed on them. I guess we will either have to adapt or die, just like the plants. Of course, trying to adapt has it own challenges. I have been slow to change my garden because of exactly what you say - if you had planted succulents, they would have all rotted. And since a garden takes years to mature, it's hard for me to know what would be best to plant now for 20 years in the future.

    ReplyDelete
    Replies
    1. Hi Holley - I suppose we try to adapt the best we can. Like Faisal said, the reliability we knew years ago has gone. I suppose there's an exciting challenge in the unpredictibility????? Certainly some people have responded in very creative ways.

      Delete
  8. Dear Catmint,
    An excellent post. I 'enjoyed' reading it if that is the correct word. Interestingly, as we plan our move back to Victoria this becomes a part of our consideration. We intend to sell our house and build a new one. We want it to be as 'green' as possible and we want to think of ways in which we can take care of our plants as well. I used to think of Victoria as being similar to the South of France but I guess with the way things are going we need to think of it in terms of southern Spain or even northern Africa!
    I do agree with Faisal when he writes that 'we can only love and do our best'.

    ReplyDelete
    Replies
    1. hi kirk, how exciting to be able to plan a new green house - whatever the weather I'm sure you will find plants that manage to survive in your new garden. I hope you'll still be blogging so we can see it.

      Delete
  9. A thought-provoking and frightening post! Thank you.

    ReplyDelete
  10. We must deal with both natural and man-made causes of climate change. Sometimes it seems that the little we do as individuals doesn't much matter, but of course it does! Regarding my garden, I am taking note of those plants, usually native, that can usually handle whatever the weather throws at them.

    ReplyDelete
    Replies
    1. me too deb - although I find many non natives are also really good.

      Delete
  11. love to see that koala again, while she didn't survive, her story lives on. The cartoon reminds me of the Millenium seed bank, combined uneasily with cryogenics.

    Someone wrote of planning for 7 (human) generations. That is a daunting prospect. I wonder what just one or two generations will bring?

    ReplyDelete
    Replies
    1. that is a fabulous interpretation of the cartoon - thank you Diana. Any excuse to re-post that koala photo, it's so beautiful, although so sad that she died. I can't imagine how people will live in the future - or rather, I can imagine a whole range of possible alternative worlds, from utopia to dystopia.

      Delete
  12. Climate change is very sobering as we each face it in our area...that is why I have moved to more native plants that hopefully will be able to stand the changing conditions and survive.

    Fascinating weather records...

    ReplyDelete
  13. What a tremendous post and eye opener. I agree, as a designer, I am tossed on what to specify to plant. It is a hardship on clients and the environment that has to support plants in harsh temperatures. I love the kindness shown the Koala. Sad for the black cockatoos. I have to let my cockatoo know he might just be a better off bird right now.

    ReplyDelete
    Replies
    1. hi donna, it must be hard as a designer, I imagine part of your job must be to educate clients as to what is possible? Are you joking, or do you really have a cockatoo as a pet?

      Delete
  14. Although I just live more than 4 years in OZ I can feel the changes. Now I am back in my hometown I feel some changes as well.

    ReplyDelete
    Replies
    1. hi diana, the climate changes so far haven't affected your brilliant vegetable growing!

      Delete

Post a Comment