Data Sources and Metrics
The 5th edition of the Research.com Best Earth Science Scientists in New Zealand Ranking was created using a comprehensive collection of bibliometric data primarily sourced from OpenAlex and CrossRef, supplemented by multiple other reputable data repositories. The bibliometric data necessary for calculating citation-based metrics was collected on January 12, 2026, ensuring that the ranking reflects the most current scholarly activity available at the time of analysis. A researcher’s position within the ranking is determined based on their D-index (Discipline H-index), a specialized metric that considers only the papers and citation metrics strictly within the Earth Science discipline. This approach ensures that the evaluation is both precise and relevant to the specific field.
Scope of Research and Eligibility Criteria
Our extensive analysis began with a pool of 279,971 scientist profiles identified across a broad spectrum of bibliometric databases, covering all research disciplines. From this, a focused cohort of 103 scientists specializing in Earth Science was examined in detail. To qualify for inclusion in the ranking, a scientist’s D-index had to meet or exceed a threshold of 30, with the majority of their tier publications clearly situated in Earth Science. Additionally, the candidate’s awards and significant achievements in the field were considered to further validate their impact.
The D-index thresholds used for selection are calibrated in increments of 10 based on the total estimated number of scholars in each discipline, with the intent to consistently capture the top 1% of leading experts. A criterion is also applied ensuring that the difference between a scientist’s general H-index and their Earth Science-specific D-index does not exceed 30%, guaranteeing alignment between their overall impact and discipline-specific contribution.
Verification and Methodological Rigor
Our research team recognizes that raw bibliometric data alone cannot serve as an absolute measure of a scholar’s output. Consequently, all scientist profiles included in the ranking underwent a rigorous manual verification process. This involved cross-correlating each profile against publications from a wide array of trustworthy sources to confirm accuracy and authenticity.
While the number of papers published in prominent journals and conference proceedings does not directly influence a researcher’s ranking position, it remains a valuable secondary indicator of their contribution to Earth Science. The ranking is firmly established on each scientist's D-index, calculated from robust data retrieved from OpenAlex and CrossRef, two of the most prominent bibliometric databases trusted by the research community worldwide.
For a detailed account of the methodology and underlying principles, we encourage readers to visit our methodology page.
Research.com’s Mission and Vision
This ranking embodies Research.com’s broader mission to inspire researchers, companies, and policymakers globally to monitor and understand the direction of leading scientific expertise. Our goal is to provide an accessible platform for the scientific community and stakeholders to identify and connect with the foremost experts in specific research areas, countries, and institutions. Through this, we aim to foster informed collaboration, decision-making, and progress across the landscape of Earth Science and beyond.
