Term 1 Isotopes & Climate Vocabulary

Question 1

Isotopologues

Answer 1

Molecules differing in isotopic composition alone

Question 2

Isotope Ratios

Answer 2

Ratios comparing the abundance of isotopologues

Question 3

Stable Isotopes

Answer 3

Isotopologues that do not undergo radioactive decay (but may be radiogenic)

Question 4

Isotope Ratio Mass Spectrometry

Answer 4

Method using fluid states to analyse stable isotope ratio of a sample through ionisation

Question 5

Delta Notation

Answer 5

The relative difference of isotopic ratios of a sample and a reference standard (reported in parts per thousand, ‰)

Question 6

Isoscapes

Answer 6

The geospatial patterns of isotopologues used to predict isotopic ratios

Question 7

Rayleigh Fractionation

Answer 7

The evolution of a multi-phase system in which one phase is continuously removed through fractional distillation (the separation of a mixture into its components)

Question 8

Global Meteoric Water Line

Answer 8

The line formed from the relationship between δ2H SMOW and δ18O SMOW, describing global annual average relationship between H and O isotope ratios in natural meteoric waters (water derived from precipitation)

Question 9

Dansgaard-Oescherger Periods

Answer 9

Times in which climate switched between cold and ‘warm’ glacial climates, with rapid warming and slow cooling

Question 10

Planktic/Planktonic

Answer 10

The part of the ocean above the photic zone

Question 11

Benthic

Answer 11

The part of the ocean under the photic zone, including the seafloor

Question 12

Upwelling Zones

Answer 12

Regions in which colder, denser water sinks to displace warmer water

Question 13

Foraminifera

Answer 13

Microscopic protists characterised by a streaming granular ectoplasm for catching food and a calcite shell (test)

Question 14

Ice Volume Effect

Answer 14

Water is precipitated onto land, varying the distribution of lighter isotopes

Question 15

Conodonts

Answer 15

The first vertebrates with mineralised skeletal elements, which developed during the Cambrian and thrived in the Silurian

Question 16

C3 Plants

Answer 16

Plants using the Calvin cycle to photosynthesise, with CO2 taken in to produce PGA, occurring in cool, wet climates

Question 17

C4 Plants

Answer 17

Plants using the Hatch-Slack cycle to photosynthesise, in which CO2 passes into the leaves to create oxaloacetic acid, occurring in hot, dry climates

Question 18

Dendrochronology

Answer 18

The scientific method of dating and correlating tree rings to establish the exact time of formation

Question 19

Latewood

Answer 19

Wood grown at the end of a season, typically darker and denser