The effects of climate change are being seen across the globe, with extended periods of oceanic warming known as marine heatwaves increasing in frequency and duration. A marine heatwave is characterised as occurring "when seawater temperatures exceed a seasonally-varying threshold (usually the 90th percentile) for at least 5 consecutive days." (Marineheatwaves.org).

Marine ecosystems and coastal communities are affected by these unusually warm waters. Since Aotearoa New Zealand has the ninth-longest coastline in the world, it is especially at risk for marine heatwaves. Our fisheries and aquaculture industries are worth more than $4 billion annually. Marine heatwaves can fuel extreme weather, disrupt ecosystems, and threaten marine biodiversity.

 Through the intensity scale, the Moana Project's forecast below shows which coastal areas are experiencing marine heatwaves and to what extent. This forecast can help industries and communities that depend on the ocean, like fishing, tourism, and recreation, make better decisions. By keeping track of marine heatwaves, we can learn more about how they affect our coastal ecosystems and economies and work to make them stronger.