A proposed automated instrument to analyse coral reef sample (Spectral luminescence scanner)

Corals provide annual to sub-annual records of sea-surface property variation. To determine the hydrological changes as a function of river discharge, rainfall or terrestrial influence, coral skeletal luminescence effectively captures seasonal, inter-annual and long-term variability. The coral luminescence measurement has implications to climatology and oceanography. As part of the scientific programme on high-resolution reconstruction of climate changes on the centennial time scales, corals samples were collected from the Laccadive Islands, the Andaman Islands and the Gulf of Kutch. Coral reefs like all ecosystems record changes over time and are affected by surface ocean processes modulated as a function of climate change. To decipher the past variability of climate, corals provide an ideal archive for high resolution reconstruction of climate change. To realise this objective, a proposal is made for an automated instrument based on spectral luminescence technique described by Grove et al. [7] which provides spectral ratios based on secondary emissions(G/B). The spectral luminescence varies as a function of coral band density and thereby reflects the dilution of seawater with freshwater and thus correlates with geochemical coral proxies of terrestrial runoff or river flow. This can further be related to temporal variation of rainfall. The proposed instrument can analyse coral reef sample of specific dimension and provide spectral ratios of different regions selected by the user in the sample.