New Zealand 2003 - North Island

For this one week trip in 2003 we hired a campervan and drove around the North Island of New Zealand, starting in Auckland and ending in Wellington. New Zealand is a very actively volcanic group of islands.
A special highlight was visiting the town of Wakatane where we caught a boat, the PeeJay, out to Waakari / White Island, currently New Zealand's most active volcano.

It is is a stratovolcano with an elevation of 321m and is located 48km offshore in the Bay of Plenty.

The volcano has lava eruptions and phreatic explosions or eruptions which involving the island's ground water interacting with magma.

Smelly, hot and steamy sulphur gases are always spewing from the craters and fumaroles on the island and can be dangerous and unpredictable, so as required, we donned gas masks and signed all of the waivers and then walked around and explored with a very informative guide.



The water level in the lake has been rising and the guide was indicating this may one day form part of a phreatic explosion. The last big blow up and eruption was around 2001. The colour of the water is amazing like a green mineral.
A fumarole is an opening in the earth around the volcano and you can clearly see all the steam and gases spewing out of them.

Atmospheric gases initially come from the earth's interior. Gases within magma are dissolved because of high pressures beneath the earth's surface, but reduced pressure at the surface allows dissolved gases to expand and escape. 70 to 95 percent of all eruption gases are water vapour which is beneficial, adding to the earth's water supply.

Other gases emitted are carbon dioxide, sulphur dioxide and traces of nitrogen, hydrogen, carbon monoxide, sulphur, argon, chlorine and fluorine. These gases do good and bad with their complex re-inventions.

Sulphur dioxide emitted by volcanoes can help cool the earth's surface as the gases are converted by the sun's rays reacting with water vapour, forming acid rain and sulphuric acid aerosols (volcanic ash).

The aerosols reflect the sun's rays, having a cooling effect and they remain in the air long after solid ash particles have come back to the ground, but also contribute to global warming by in turn giving off carbon dioxide into the atmosphere, adding to the greenhouse effect. These gases, in particular, sulphur dioxide, are said to have the greatest impact on Earth's short-term weather patterns or long-term climate change. Every time there is an eruption rich in sulphur dioxide, the aeorosol layer is replenished. Emissions of the volcanic ash aerosol and sulphur dioxide may cause an impact on air traffic and eruption monitoring is peformed via satellite based instruments to assist in planning air line routes if gas emmissions exceed an acceptable limit.

The carbon dioxide behaves like a glass shield over the Earth. The sun's rays can penetrate the carbon dioxide gas but the carbon dioxide shield stops heat from escaping. Volcanoes contribute around 110 million tonnes of carbon dioxide a year via their eruptions and activity. Man then is worse - his contribution is about 10 billion tonnes per year!




There was a sulphur mining plant on the island until closed down in 1914 after a crater collapsed and the lahar killed 10 of the plant's workers.








The waters around the island are understandably warmer than normal and the sea life is thriving. The boat had an underwater camera giving us a different view of the island with very healthy waters housing kelp beds and schools of fish and many seals bask on the warm rocks during the day.

We also visited Rotorua and its 'boiling mud' sulphur pools at Waiora Spa, Hell's Gate, New Zealand's most active thermal reserve.








Our travels also included visits to the Waitomo Caves, where you can see the amazing glow worms, a jet boat ride at Huka Falls and the City of Auckland. We saw the Kea birds and the New Zealand Kiwi, a nocturnal and very endangered native bird. We visited the Auckland aquarium and watched penguins playing about there.



The scenery is amazing on the North Island and supposedly not as pretty as the South Island, so maybe that's another visit at another time. Hiking or 'tramping' is one of the favourite pastimes in New Zealand and campervan trips are another popular NZ habit.

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