I spent the last two weeks touring the North Island of New Zealand. The country is split into two large islands of comparable size and lots of smaller islands with interesting characteristics. Some islands are even ancient and active volcanoes.
My trip took me from Auckland to Wellington and back. It was a great adventure but I couldn’t help notice just how brown everything is. This is in stark contrast to a few months ago when the landscape consisted of rolling green hills covered in grass and other vegetation. Indeed, last November, I was wondering if it would ever stop raining.
Now Auckland, New Zealand’s major city, is reporting its 48th day without significant rainfall. There have been a few splashes here and there but for the most part the city is now in a severe drought. North of Auckland, some of the smaller towns are in danger of running out of water entirely. South of Auckland, in the Waikato where I am presently living, we haven’t seen significant rain in about the same amount of time.
So lush pastures are turning brown as the grasses dry up and farmers are beginning to worry about the potential impact on their livestock as food is becoming increasingly scarce.
At the same time, on the west coast of the South Island communities have been battered with rain storms resulting in floods. Driven in part by the ex-tropical cyclone Usei, the rains have left some communities stranded as roads have washed out.
Is all the normal?
It is a question many New Zealanders are asking themselves. In a country which prides itself on generating all of its electricity from non-fossil fuel based sources (wind farms, geothermal and hydro dams provide the load), it would seem climate change is having a significant impact.
The present drought conditions are not out of the ordinary. As one meteorologist working for the National Institute of Water and Atmospheric Research put it, “what we are seeing is within the range of normal variation” but as climate scientist James Renwick states “it has now been 35 months since New Zealand had a month with below-average temperatures." That should concern anyone wanting a drink of water or a regular shower.
Can we trace New Zealand’s weather to climate change?
It would appear to have a lot to do with conditions which would normally occur during an El Nino except there is no El Nino this year. It is also driven by the Indian Ocean Dipole (IOD) which helped plunge Australia into its recent bout of record high temperatures and the bush fire crisis. The IOD has been in a strong positive phase for the past few months. It created a temperature difference across the tropical Indian Ocean which is impacting the climate throughout the region.
Another big driver influencing the weather is a negative Southern Annular Mode but both it and the IOD were expected to switch back to neutral returning the regional climate to expected norms. It hasn’t happened. Further there is a stable ridge of high pressure situated off the west coast of the North Island which has been blocking the approach of wind and rain for weeks.
Essentially, the normal climate the North Island would be expecting at this time of year is not going to happen. Instead, it is dry. Very dry.
Of course, New Zealand is not alone in its extreme weather. There is major flooding in the United Kingdom, the cold winter striking most of North America and the record high temperatures being recorded in parts of Antarctica. And while all of these can be catalogued as “weather phenomena”, there is little doubt they are the by-products of our changing climate.
Or as climate researchers put it – they can now detect the fingerprint of global warming in daily weather observations at the global scale.
And as much as we would like to claim it is not our fault, it is increasingly evident that human activity is having a major impact. By altering the balance of carbon dioxide and other greenhouse gases in the atmosphere, we are driving the changes to our climate. Further, the changes are engaged in positive feedback. The more ice melting from the Antarctic, the less sunlight is reflected and the warmer the oceans get resulting in more ice melting from the Antarctic.
Some people want to deny our role or, at least, argue there is nothing we can do about climate change without severely impacting our standard of living. “We couldn’t live without fossil fuels?” they say.
And yet, New Zealand has been generating its electricity without employing coal or gas powered plants for a number of years. It is a great place to live, provided you don’t mind the present drought.