In search of the hard facts, Aaron Packard talks to several of Victoria’s lecturers about how cliemate change will affect us.
1. Climate…
I talked to Dr Andrew Mackintosh from the School of Geography, Environment and Earth Sciences, and Dr Gavin Dunbar from the Antarctic Research Centre.
* New Zealand is predicted to get 2-3 degrees warmer by 2080, which is perhaps a little less than the global average. (according to National Institute of Water and Atmospheric research (NIWA)).
* Such predictions are large and don’t take into account the possibility of abrupt climate change. Northern Hemisphere research has found that abrupt climate changes of 10 degrees celcius or more were fairly common during the last 100,000 years or so. These large changes in the climate occur over the course over years or decades rather than centuries. We can’t yet predict how or when this might happen, but it is a possibility. The vast majority of scientists believe that our greenhouse emissions are contributing to warming today, and the results of this enormous unprecedented ‘experiment’ are not fully understood because the global climate system is complicated and non-linear.
* Brett Mullan and Jim Renwick at NIWA argue that we are more likely to see El Nino events, bringing south westerly winds from the sub-Antarctic regions. This will bring increased amounts of rain to the west coast, and more frequent periods of drought on the east coast. New Zealand sits on the boundary between sub-tropical and subantarctic currents and so will experience a real mixture of conditions.
* We will probably see a different pattern in the Northern Hemisphere to what occurs here in the Southern Hemisphere.
Professor Lionel Carter, a Marine Geologist from the Antarctic Research Centre.
Why should we care about what we might be doing to the oceans?
* NZ is a maritime nation, with the 4th largest exclusive economic zone in the world, and have control over a huge expanse of ocean. Our oceans are affected by both sub-tropical and sub-antarctic currents and a lot of research is looking at how these two interact.
* NZ is a maritime nation, with the 4th largest exclusive economic zone in the world, and have control over a huge expanse of ocean. Our oceans are affected by both sub-tropical and sub-antarctic currents and a lot of research is looking at how these two interact.
* Acidification (when there is too much CO2 absorbed in the water, turning it acidic) is also a global issue. There is evidence that the pH of the ocean is changing, but the science is not as good as it could be.
* Globally, oceans are warming. Locally, however, the Antarctic-tropical interaction has meant that the oceans around NZ have actually cooled. This is due to melting of the Antarctic ice sheet and stronger El Nino events. This ultimately means that the production of marine plankton will change. Plankton are at the base of the food chain, so this will have huge repercussions for the rest of the food chain.
2. Marine…
Dr Jo Zuccarello, is a phycologist (algal specialist)
* General consensus within the scientific community is that the current quota management system that New Zealand uses is not sustainable. Fish stocks are in decline as a result of industrial fishing.
* It is commonsense that due to overfishing we are reducing the number of fish species that we get to eat. So we are going to have to move down the food chain! Soon we’ll be eating jelly fish!
* There still remains much to be learnt – to put it into perspective, the oceans cover approximately 70% of the earth’s surface. A lot more work needs to be undertaken so that we can have a better understanding of what goes on under the surface. NIWA has recently been mapping areas of the sea-mounts. They have discovered geothermal vents that they previously didn’t know existed, which are literally teeming with unique life. Practises such as bottom trawling quickly destroy such biodiversity ‘hotspots’.
3. NZ Flora…
Dr Sean Weaver is a lecturer in Environmental Studies, School of Geography, Environment and Earth Sciences
What are the two most pressing issues that face NZ’s native vegetation?
1. Climate Change
2. Introduced pests (eg possums, deer, goats etc)
How much do we have left?
800 years ago, New Zealand had approximately 80% forest coverage. In 800 years we have done what took Europe 8000 years. 23% forest coverage remains, and this is concentrated in alpine areas. Around 14% of the original lowland forest is left.
To what degree is human activity impacting on our native flora
* In 1992, the Forest Amendment Act was introduced, putting a stop to all clear felling of native forests on all land.
* In 2000, the government stopped all logging on crown land. So we have thankfully reached a point where we have recognised the need to protect native forests in New Zealand.
* The place where forest conservation is sorely needed now is tropical rainforests – they are coming down at a rate of 16 million hectares per year!
4. Native Fauna…
Dr Stephen Hartley, is a Population Ecologist from the School of Biology
* Loss of habitat one of the most pressing issues.
* We’ve lost 32% of our endemic birds, 3/64 of our reptiles and possibly 11/2300 known endemic plant species.
* On a positive note, New Zealand has a high proportion of land that has been designated national reserve, compared to most other countries.
5. Water…
Cath Wallace is a Senior Lecturer in Public Policy and Environmental Economics.
How secure is our supply of clean water?
* It is becoming more and more polluted, and we are running down our stocks due to bad land use, sedimentation and agriculture.
* The three biggest issues that we face in regards to freshwater are land use, sedimentation and how we allocate water.
How likely is that our water is going to get privatised?
The Government has said that they will retain state ownership of our waterways.