Regional scale high resolution δ18O prediction in precipitation using MODIS EVI

PLoS One. 2012;7(9):e45496. doi: 10.1371/journal.pone.0045496. Epub 2012 Sep 19.

Abstract

The natural variation in stable water isotope ratio data, also known as water isoscape, is a spatiotemporal fingerprint and a powerful natural tracer that has been widely applied in disciplines as diverse as hydrology, paleoclimatology, ecology and forensic investigation. Although much effort has been devoted to developing a predictive water isoscape model, it remains a central challenge for scientists to generate high accuracy, fine scale spatiotemporal water isoscape prediction. Here we develop a novel approach of using the MODIS-EVI (the Moderate Resolution Imagining Spectroradiometer-Enhanced Vegetation Index), to predict δ(18)O in precipitation at the regional scale. Using a structural equation model, we show that the EVI and precipitated δ(18)O are highly correlated and thus the EVI is a good predictor of precipitated δ(18)O. We then test the predictability of our EVI-δ(18)O model and demonstrate that our approach can provide high accuracy with fine spatial (250×250 m) and temporal (16 days) scale δ(18)O predictions (annual and monthly predictabilities [r] are 0.96 and 0.80, respectively). We conclude the merging of the EVI and δ(18)O in precipitation can greatly extend the spatial and temporal data availability and thus enhance the applicability for both the EVI and water isoscape.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Climate*
  • Geographic Information Systems
  • Hydrology
  • Models, Theoretical
  • Oxygen Isotopes / chemistry*
  • Taiwan
  • Water / chemistry*

Substances

  • Oxygen Isotopes
  • Water

Grants and funding

Funding provided by National Science Council of Taiwan, Grant Number: NSC98-2119-M024-001 & NSC96-2621-B024-001 (http://web1.nsc.gov.tw/), Taroko National Park of Taiwan, http://www.taroko.gov.tw/, and Academia Sinica, Grant Number:AS-BRC-PI quota (http://www.sinica.edu.tw/index.shtml). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.