| Summary: | This chapter provides an overview of New Zealand's modern climate, followed by a summary of evidence for long-term climate changes on land and the surrounding oceans during the Quaternary. Natural archive palaeodata show details about evolving climate conditions for the last 2.6 million years, which we use to outline a perspective about vastly different base climate states (interglacials and glacials) that impacted New Zealand in the past. A framework based on long-term marine sediment records indicates New Zealand's climate was significantly impacted by the Quaternary ice age cycles, which helped to drive changes in marine currents, gyres, and boundaries. The abundance of pollen records on land highlights past vegetation dynamics that can be related to earth orbital changes, in addition to influences of important climate drivers like ENSO and SAM on finer timescales. Syntheses for full glacial and interglacial climate, for interstadial intervals (climate conditions between glacial and interglacial), and for transitions into and out of past ice ages indicate multi-centennial to millennial-scale variability impacted New Zealand. Southern Alps glacial chronologies have been recently augmented with cosmogenic dating and, when paired with quantitative climate reconstruction techniques and modeling, provide new avenues to test hypotheses about regional and global teleconnections. For the base climate states and transitions that are examined here, there appears to be support for New Zealand's continued (but variable) climate connections to Antarctica, to the lower latitudes of the Southern Hemisphere, and to the wider integrated global climate system.
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