Fishing for data: commercial fishers help monitor rising temperatures in coastal seas

Commercial fishers are playing a key role in helping monitor rising temperatures in coastal seas

Commercial fishers are playing a key role in helping monitor rising temperatures in coastal seas as the world’s oceans continue to take up more than 90% of the excess heat generated by greenhouse gas emissions. This has led to a global average warming of 0.88℃, which has serious implications for marine ecosystems, ocean circulation, heat distribution, atmospheric weather systems, and ultimately the health of our planet.

While scientists have been measuring subsurface ocean temperatures around the world, there has been a coastal gap in those measurements. This is where fishing, aquaculture, recreation, and ocean managers need good data the most. To address this, the MetService’s Moana Project has partnered with the commercial fishing sector to deploy sensors on vessels nationwide to gain insights into how ocean temperatures are changing near the coast.

Temperature measurements are crucial for understanding and accurately predicting extreme events such as severe storms and unusually warm coastal waters, which can have serious economic and societal impacts. For instance, Aotearoa New Zealand has been hit by extreme rainfall and persistent marine heatwaves over the past few years, severely affecting marine life, fisheries, and aquaculture. Increased ocean temperatures can exacerbate severe weather events like Cyclone Gabrielle, contributing to conditions for intense rainfall and potential devastation.

To prepare for a changing climate and provide early alerts for extreme events, there is a need to monitor temperature changes below the ocean’s surface. Traditionally, these measurements have been expensive and often require oceanographic research vessels to deploy instruments. However, the Moana Project has developed the Mangōpare sensor in partnership with Nelson-based company ZebraTech. This small, lightweight, robust, and accurate temperature sensor attaches to commercial fishing gear, making it easier to crowdsource ocean observations.

Thanks to more than 200 skippers and crew who volunteered to take part, there are now 300 sensors on commercial fishing vessels, providing more than one million subsurface observations a month from across Aotearoa New Zealand. The sensor attaches to any type of fishing gear and automatically collects ocean temperature and depth measurements through the water column. This information is then automatically sent to the cloud, quality checked, returned to the fisher collecting it, and incorporated into MetService ocean forecasts.

The temperature observations collected are used to improve ocean forecasting models and verify the depth of marine heatwaves around Aotearoa New Zealand. Sensor data helps improve three-dimensional predictions of ocean temperature, currents, and sea level, similar to how a weather station on land collects real-time data that improves weather forecasts. These forecasts are used to prepare coastal communities for approaching storms, optimize fishing, and alert aquaculture to extreme ocean temperatures.

Moreover, scientists use the sensor data to understand how ocean temperature affects marine ecosystems, particularly in areas affected by severe marine heatwaves leading to changes in fish distribution and impacts on sensitive species. The sensor provides measurements exactly where fishing occurs, helping fishers make sense of changes in their catch.

The continuation of this system will lead the way toward informing a climate-resilient blue economy and understanding the coastal ocean, providing measurements that will only become more critical in the coming years. This approach demonstrates how we can solve critical environmental issues by breaking down traditional barriers and partnering with technology innovators, the commercial fishing sector, citizen scientists, and researchers from across New Zealand.

Source: The