Planktonic foraminifera and their proxies for the reconstruction of surface-ocean climate parameters

Planktonic foraminifera are useful organisms to assess the surface
oceans role in climate change, due to their upper water
column habitat, calcium carbonate mineral structure, and
preservation in the deep-sea sedimentary record. Carbonate
sediments rich in the calcitic shells of foraminifera are abundant
in both space and time, which allows their use in an array of paleoceanographic
studies over time scales ranging from
decadal to glacial-interglacial, as well as beyond and between.
Here we review the most important proxy methods to reconstruct
surface-ocean climatic variables using planktonic
foraminifera. These methods include assemblage-based and
geochemical-based (both isotopic and elemental) approaches.
The natural emphasis is on temperature, the most important
climatic parameter of the surface ocean, although related
physical, chemical, and biological properties are addressed as
well, such as salinity, productivity, nutrient utilization, weathering,
circulation, and oceanic C-system properties including alkalinity,
pH, and [CO3
2-]. In our systematic evaluation of each
foraminiferal proxy, we provide the basis for each method, brief
examples, and a glimpse into the future, when current research
needs will hopefully be met.