STEMxm 26: Paleo-Oceanography with Jennifer Walker

Jennifer Walker STEMxm

STEMxm Episode 26 – 
Paleo-Oceanography with Jennifer Walker
This is the 4th episode in a series touching on climate change careers and research. Check out the others here:

Envirothon – Environmental resources research competition for highschoolers

Related Headline: Sea level rise in 20th century was fastest in 3,000 years, Rutgers-led study finds

Rutgers Department website where Jennifer is completing a PhD


Research concepts discussed with Jennifer on episode 26

  • Proxy – “In paleoclimatology, or the study of past climates, scientists use what is known as proxy data to reconstruct past climate conditions. These proxy data are preserved physical characteristics of the environment that can stand in for direct measurements. Paleoclimatologists gather proxy data from natural recorders of climate variability such as tree rings, ice cores, fossil pollen, ocean sediments, corals and historical data. By analyzing records taken from these and other proxy sources, scientists can extend our understanding of climate far beyond the instrumental record.”
  • Foraminifera are a species that are used as proxy indicators for scientists like Jennifer to study historic sea level changes. “Foraminifera (forams for short) are single-celled protists with shells. Their shells are also referred to as tests because in some forms the protoplasm covers the exterior of the shell. The shells are commonly divided into chambers which are added during growth, though the simplest forms are open tubes or hollow spheres. Depending on the species, the shell may be made of organic compounds, sand grains and other particles cemented together, or crystalline calcite.” You can read a peer-reviewed article about that here.
  • Sediment Stratigraphy – “The branch of geology that seeks to understand the geometric relationships between different rock layers (called strata), and to interpret the history represented by these rock layers.”
  • Marsh – “A marsh is a type of wetland, an area of land where water covers ground for long periods of time. Unlike swamps, which are dominated by trees, marshes are usually treeless and dominated by grasses and other herbaceous plants.
    • Herbaceous plants have no woody stem above ground, and they grow and die back on a regular cycle. Herbaceous plants can be annuals (which grow anew every year), biennials (which take two years to complete their life cycle), or perennials (which take more than two years to complete their life cycle.)
    • Marsh grasses and other herbaceous plants grow in the waterlogged but rich soil deposited by rivers. The plants roots bind to the muddy soil and slow the water flow, encouraging the spread of the marsh. These watery pastures are rich in biodiversity.
    • There are three types of marshes: tidal salt marshes, tidal freshwater marshes, and inland freshwater marshes. Marshes are also common in deltas, where rivers empty into a larger body of water. Although all are waterlogged and dominated by herbaceous plants, they each have unique ecosystems.”
  • Glacial isostatic adjustment – the ongoing movement of land once burdened by ice-age glaciers.