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Climate change

The UN states that “climate change refers to the long-term shifts in temperatures and weather patterns. Such shifts can be natural, due to changes in the sun’s activity or large volcanic eruptions. But since the 1800s, human activities have been the main driver of climate change…”

Although burning fossil fuels is largely blamed for climate change, it is important to note that climate change is not just about rising temperatures; it is a breakdown of the Earth’s interconnected systems. For example, our oceans act as a vital regulator, but heavy pollution and acidification are damaging their ability to balance the climate. When the ocean’s health falters, it triggers a chain reaction that disrupts weather patterns and ecosystems globally. Because all life is linked, a crisis in our seas inevitably becomes a crisis on land. We aren’t simply “warming” the planet—we are breaking the natural cycles that keep it stable.

So, much of Te Ipukarea Society activity touches on climate change, whether it is helping clean up the beach, education on plastics reduction, working to protect biodiversity, or raising the risks of deep-seabed mining.

Geotextile sand container (GSC) wall

Climate Change Cook Islands invited Kelvin Passfield to guide students from the Pa Enua Tokerau (Northern Group islands) on a site visit to the geotextile sand container (GSC) wall constructed in Avana in 2021. This educational effort introduced students to alternative, innovative coastal protection methods highly relevant to their home islands.

Purpose

The goal is to trial this geotextile technology in a northern atoll setting, allowing the community to witness its benefits firsthand. If successful, it may serve as a low-cost, sustainable model for other northern islands addressing the growing threat of climate change and sea level rise.

Highlights

The GSC wall serves as a practical solution particularly suited to the low-lying coral and sandy environments of the northern atolls. Unlike the rocky southern islands, the north lacks the volcanic materials required for conventional seawalls. The GSC system is designed to utilise the readily available abundance of sand.

These strong, sand-filled fabric tubes are strategically placed to reduce wave energy and limit coastal erosion. The system is both cost-effective and blends more effectively with the natural environment than concrete or rock barriers.

Image gallery
In 2022, even without a cyclone or heavy rain, exceptionally high tides undermined foundations and uprooted plants as the sea washed away the sand.
Climate change impacts: extreme wave action has relocated beach sand to build up on the stream bank and completely block the culvert stopping the stream’s natural flow.
While rock walls are often used to combat erosion, this Avana site was chosen to test the effectiveness of sandbags as a more flexible coastal protection measure.
Before the sandbags can be placed, the site must be prepared. This involves digging out the area to ensure the bags sit securely against the shoreline.
These large-scale geotextile tubes are engineered for durability. The installation process is significant, requiring heavy machinery to fill and position them securely along the coastline.
The bags are strategically placed to absorb wave energy and reduce erosion. To reinforce this, we also plant local vegetation, which helps bind the sand and stabilise the coastline.
It is vital for our youth to understand how healthy waterways maintain the balance of our environment. A resilient ecosystem is our best defence against the impacts of climate change.
Community action: Muri Environment Care (MEC) works to clear local waterways and mentor the next generation. TIS partners MEC on projects to protect our local environment.
While clearing weeds opens the waterway, planting the banks is essential for long-term stability. The roots act like a natural net, binding the soil and keeping our riverbanks strong.
Plants are carefully selected for their root strength: Vetiver grass reaches deep to anchor the bank, while Sedge uses its dense, fibrous roots to bind the topsoil and prevent surface erosion.
Much of the work undertaken by MEC is voluntary. While it visibly beautifies the area, it serves a deeper purpose: restoring the health and resilience of our waterways.
Stream restoration is essential to protect our lagoons, but it is a constant task. To support these efforts, visit the MEC website and find out how you can help.