The Tasman Sea heat wave


A major heatwave has arrived in New Zealand, and its signature is big enough to be picked up on satellites.

But this heatwave is different, in that it is not happening in the air. Whilst it is certainly true that parts of the South Island are experiencing very warm and in some cases, record breaking, temperatures, the source of heat is different. A muggy warm northerly airflow over New Zealand is dragging tropical air down from the Coral Sea.

The heatwave I am talking about is in the Tasman Sea. At the Port of Lyttelton on the east coast of the South Island it was 17ºC in January 2017. A year later it is 22ºC. Atmospheric imaging of the Tasman Sea shows that much of its area as well as the seas around the rest of New Zealand are generally warmer than they were in 2017.

Currently sea temperatures in the Tasman Sea are about 6ºC above normal. National Institute of Weather and Atmospherics (N.I.W.A.)data shows that not since before 1900 has there been a year when sea water temperatures in the Tasman Sea were this high. Likewise, the American National Oceanic and Atmospheric Administration (N.O.A.A.) thermal imagery shows a large red blob in the Tasman basin and the rest of New Zealand surrounded by yellow.

The same thermal anomalies in the sea that are causing this heat wave are also the same ones that enable low pressure systems to suddenly deepen rapidly or even explosively and throw up strong storm like conditions. It is over these seas that features such as the January 2017 weather bomb event, where a low pressure system over the Tasman Sea suddenly became a significant storm with 300 millimetres of rain at Arthurs Pass and various locations along the Southern Alps and West Coast in 24 hours and storm force winds in many locations.

The heatwave might be good for people seeking some nice warm seawater to swim in. However it is potentially stressful for marine life and there are concerns that it might be linked to any near future die offs, of shell and kelp forests. The warm sea water has also been linked to the earlier than normal arrival of blue bottle jellyfish.

How long this warm sea water lingers for is unknown. An approaching low pressure system in the Tasman Sea is expected to deliver heavy rain to the West Coast on Wednesday with showery conditions in its wake across New Zealand.

The joys of living in a maritime climate.

Storm reminds New Zealand of importance of coastal protection


Sand dunes at New Brighton in 2009. R. GLENNIE

When I was at intermediate school in 1992 we had a day off at the end of term due to a large low pressure system coughing up a heavy snow event. Aside from causing a complete province wide shut down, the tail end of the storm brought a massive southeasterly swell that battered the gently sloping sandy beaches of Pegasus Bay and cut away metres of slope. Over the coming months and maybe years, long shore drift moved the sediment back into place. But there was a lesson for any coastal management planner and physical geographer in this: protect your coastal communities or pay the price.

Decades later and having watched another battery of New Zealand beaches, this time caused by a sub tropical depression turning into a deep low that drove huge waves ashore along the eastern coast line of New Zealand, I cannot help but wonder if we have learnt anything?

If we look at the damage left behind and the grief that even 2 days after it began to move away, it caused those local communities, I would guess the answer to the question is: no. Despite the seas having been across the roads before, despite previous erosion problems, it seemed to escape peoples minds that these were not such big storms.

The coastal geographers have been warning New Zealanders for decades. Way back when I was in high school there was a section of the community in Christchurch who wanted to remove the sand dunes in Christchurch because they were affecting property prices. No one wanted to know about the potential for storm surge during large southerly storms or sub-tropical lows. Nor did they want to know about the tsunami risk posed by earthquakes both near field and far field. To them, these were things that happened elsewhere.

Few will forget the appalling video clips from Japan showing the sea sweeping all before it during the huge tsunami that followed the magnitude 9.0 11 March 2011 earthquake. Watching entire coastal communities succumb to the ferocious power unleashed by these waves is not an easy watch. And now there is no doubt among coastal communities that we have to be prepared for tsunami. But what about the storm surge from weather events that pass through every few years or so? Especially when they virtually demolish coastal roads and flood whole communities?

Christchurch seems to have headed the warnings to leave natural coastal protection alone. Whilst plans for revitalizing New Brighton continue talking about the residents, and making it a more attractive area for tourists, few now seem to have the appetite that existed in the late 1990’s for removing the dunes.

But with potential climate change and change in local marine topography over time, the behaviour of the sea will change. The tide that used to stop two metres down the beach might now be lapping the upper edge of the beach. Wave energy on the coast helps to determine the type of beach one gets – will it be gently sloping like New Brighton with its dunes or a high energy environment where no one can safely swim, such as Birdlings Flat? Are you right at sea level on the coast, or do you have a couple of metres altitude to protect you from coastal flooding?

One might have ignored those questions in the past, but can you ignore them in the future?

Protecting the whitebait fishery in New Zealand


Whitebait are a New Zealand delicacy. Every year hundreds of people try their hand at catching the tasty translucent morsels that enter our coastal waterways. On the market, a kilogram of whitebait may fetch N.Z.$90.

Whitebait patties are how most whitebait that are caught end up. Their popularity is enduring by virtue of the relative ease and speed of making them. They were the entree at the A.P.E.C. 1999 State Banquet held for the then United States President Bill Clinton and the Chinese President Jiang Zemin.

But whitebait are in danger of extinction. Their immense popularity, damage to their habitat and (this is debatable)over fishing of the delicacy, which have five subspecies in New Zealand – climbing galaxias, common galaxias, banded kokopu, shortjaw kokopu and giant kokopu have brought about severe challenges for a popular recreational past time. This has brought with it, talk of possibly closing the fishery for a period of one or two years during which there is a complete ban on whitebaiting, with the idea being that whitebait would be able to regain some of their population.

Whitebait habitat damage, and in particular their spawning grounds is the most serious threat they face. A spawning ground might be only a couple standard glass houses in area, but in that area tens of thousands of whitebait will be depositing their eggs, and the destruction of that one spawning ground might be the difference between whether or not that particular river/stream/creek/estuary/lagoon has a meaningful whitebait population the following year.

I and my father whitebait each year. We have no problems with compliance and follow local regulations specific to the Canterbury area and fisheries. We do it because we enjoy eating whitebait and are not there to make a profit from doing so, which some are – our purpose has always been to put food on the table, which is what I believe all hunting and fishing should be about. We do not leave any litter or other debris behind that might enter their habitat and cause adverse effects.

Pollutants entering the habitat – cigarette butts, plastics, and so forth – are another threat that needs to be considered. This is a general common pollution issue that should be dealt with separately by way of enforcement action by local council rangers. Fines and – most appropriately – making the offender participate in a rubbish clean up would be a good way of getting the message across.

No quotas exist for whitebaiters. It is debatable whether there needs to be quotas. One will immediately ask, if quotas exist, how are they going to be enforced and the only answer from hard experience is by ground enforcement on the spot. There would need to be many rangers enforcing the quotas and there is a possibility that they would – like anyone involved in law enforcement – possibly have to deal with hostile people. The quota size itself would also be up for debate. Sometimes several kilogrammes of whitebait might be caught each day, and then there might be none or little for several days or even weeks – nearly all we caught this year was taken in the final week of the season.

Whitebaiters are permitted to whitebait from dawn to dusk. They are allowed nets and gobi’s (nylon fencing on poles)that extend from the net to the shore. The combined net/gobi arrangement cannot take up more than 1/3 of a channel width and must be manned at all times. A whitebait net cannot be less than 20 metres from another whitebait net. The season start time varies from one region to the next – the Canterbury one started in mid-August and ended at sunset 30 November.

I don’t want any children I might eventually have or anyone else who has children to be denied the opportunity to show them an easy and fun – albeit sometimes patience testing – mode of fishing. So, let us enjoy our whitebait, but apply a bit of common sense and protect the habitats, don’t take more than you want to use and respect the other whitebaiters who have come to try their luck.

Common sense really.

The need for a Kermadec ocean sanctuary


I was disappointed to see in the Sunday Star Times today that New Zealand First have shown resistance to the idea of an ocean sanctuary. The comments in the Sunday Star Times, which allegedly caught the Green Party unawares, point to a potential hurdle in the future that the new Government will not be able to bypass.

New M.P. and former Labour M.P. Shane Jones, who is a potential cabinet member of the new Labour led minority Government, disclosed before the election that Sealord and Talleys were bankrolling his election campaign in Whangarei. Mr Jones who has extensive links to Iwi and backs customary fishing rights under the Treaty of Waitangi and fellow New Zealand First Members of Parliament have been described as close to the fishing industry.

Given the lack of regard shown for the marine environment around the world, there is a strong case for an ocean sanctuary around the Kermadec Islands. Which is why I was pleasantly surprised when the outgoing National Government in 2015 announced that New Zealand would commit to an ocean sanctuary covering the Kermadec Islands. It would not permit mining, oil extraction or fishing. The sanctuary would cover the oceans around islands such as Raoul and Curtiss Island.

This is also why I support the need for a blue water navy. Defence policy aside, New Zealand has a vast economic exclusion zone that is prone to being raided by illegals who have no legitimate business in New Zealand waters. The proposed ocean sanctuary covering the Kermadec Islands would not be exempt from the potential ravages of these raiders. A blue water navy with appropriate surveillance, backed by a strong judicial system would show raiders that if they conduct their illegal business in N.Z. waters, there will be a price to pay.

Despite the Green Party saying that they are confident that an appropriate outcome can be achieved, I have concerns about how any agreement will be passed into law, and whether it will be effective in protecting the marine ecosystem.

 

Trump quits Climate Accord; World forges ahead


Yesterday I mentioned the role of the gases linked to climate change in causing acidification of the oceans and how it could wreck the food chain. I mentioned the potential economic consequences in Queensland of not doing more to protect the oceans.

Now United States President Donald Trump has walked away from the Paris Climate Accord. Citing the supposed economic toll to the United States if it continues working on the Accord, the United States Government has shown its preference for fossil fuels at a time when major in roads are being made into renewable fuels, more efficient methods of electricity generation and the rise of the electric car. Mr Trump has demonstrated a callous disregard for an environmental crisis where the overwhelming majority of scientists believe gas emissions from excessive fossil fuel burning is the cause of a major rise

But not all is lost. Even as the United States Government refused to have any more to do with it, a revolt is spreading across America. 61 cities decided to support the Paris Climate Accord anyway. On the world stage other big players including China, the European Union and even Australia – better known for deriding the Paris Climate Accord and the preceding Kyoto Climate Protocol – stepped up and indicated they would honour their commitments.

In New Zealand, despite the mediocre efforts made by this Government to date and the inability of the Opposition to gain traction in Parliament, the commitment to reduce our contribution to the greenhouse gas emissions equation has not changed.  In terms of going forward, I believe there are a significant range of energy sources that New Zealand could be significantly investing more into. Namely:

  • Biofuel
  • Tidal power
  • Solar

There are also a number of steps that could be taken to reduce the power footprint in New Zealand.

A Green audit done over a decade ago suggested that between 15-20% of New Zealand’s power usage was avoidable. If that is still the case today, with an installed generation capacity of 9637 megawatts, between about 7700 and 8200 megawatts would be needed if all of this could be saved.

Another step that could be taken is retrofitting. Retrofitting all large facilities such as hospitals, University buildings, airports with energy saving mechanisms such as automatic sensors which turn lights out after a certain time. If this were done with an incentive such as being able to keep the savings made by such investment, these would pay for themselves fairly quickly.

A third step that could be taken is enabling individuals who want to contribute power to the grid to do so without punishment. In January the Electricity Authority ruled against Solar Energy New Zealand, which had complained about the tariffs imposed by Unison Network Limited on retailers with residential customers on S.E.N.Z.’s network.

But overall there needs to be a blue print that could have been finished by now for looking forward into the future. We as a nation need to reduce our gas emissions just as we need to tackle the acidification from the ocean that is also aggravated by these gases.