Seafloor water temperature is generally colder and more constant than surface waters. Density-driven flow of cold salty water results in deep water ocean circulation with deep water returning to the surface in areas of upwelling with high productivity. This circulation pattern provides a relatively stable thermal environment for seafloor communities of organisms at deeper depths where little mixing occurs. While relatively stable, deep sea temperatures have been increasing, but at a slower rate in the Southern Hemisphere compared to the Northern. Annual average water temperature (degrees C per km) at the seafloor (using NZ bathymetry layer) based on methods from Ridgway et al. (2002). The oceanographic data used to generate these climatological maps were computed by objective analysis of all scientifically quality-controlled historical data from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Atlas of Regional Seas database (CARS2009: https://researchdata.edu.au/cars-2009-csiro-world-monthly/954886) at approximately 41 km (1/2 degree) resolution, using surface-pressure-corrected Argo global archives. To view a dynamic model of the change in temperature at 500m around New Zealand over 5 years see: https://vimeo.com/48991073

Reference:

Ridgway, K., Dunn, J., Wilkin, J. (2002) Ocean interpolation by four-dimensional weighted least squares—Application to the waters around Australasia. Journal of atmospheric and oceanic technology, 19: 1357-1375.

Seafloor water temperature is generally colder and more constant than surface waters. Density-driven flow of cold salty water results in deep water ocean circulation with deep water returning to the surface in areas of upwelling with high productivity. This circulation pattern provides a relatively stable thermal environment for seafloor communities of organisms at deeper depths where little mixing occurs. While relatively stable, deep sea temperatures have been increasing, but at a slower rate in the Southern Hemisphere compared to the Northern. Annual average water temperature (degrees C per km) at the seafloor (using NZ bathymetry layer) based on methods from Ridgway et al. (2002). The oceanographic data used to generate these climatological maps were computed by objective analysis of all scientifically quality-controlled historical data from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Atlas of Regional Seas database (CARS2009: https://researchdata.edu.au/cars-2009-csiro-world-monthly/954886) at approximately 41 km (1/2 degree) resolution, using surface-pressure-corrected Argo global archives. To view a dynamic model of the change in temperature at 500m around New Zealand over 5 years see: https://vimeo.com/48991073

Reference:

Ridgway, K., Dunn, J., Wilkin, J. (2002) Ocean interpolation by four-dimensional weighted least squares—Application to the waters around Australasia. Journal of atmospheric and oceanic technology, 19: 1357-1375.