For this edition, the bibliometric data used to calculate the citation-based metrics were collected on January 12, 2026. A scientist’s position in the ranking is determined by their D-index (Discipline H-index), a discipline-specific adaptation of the conventional H-index. The D-index only accounts for papers and corresponding citation metrics strictly within the examined discipline—Environmental Sciences—ensuring an accurate reflection of expertise and impact within this specialized domain.
Scope of Research and Selection Criteria
In developing the ranking, an extensive dataset encompassing 279,971 scientist profiles drawn from a variety of bibliometric sources was analyzed across all disciplines. Among these, 799 scientists specializing in Environmental Sciences were identified and evaluated.
To qualify for inclusion in the Environmental Sciences ranking, scientists were required to meet a minimum D-index threshold of 30, ensuring recognition of sustained and impactful research output. Additionally, a majority of their tier publications needed to be within the Environmental Sciences domain, further validating disciplinary focus. Beyond bibliometric parameters, scientists’ awards and achievements specifically related to Environmental Sciences were also taken into consideration as qualitative indicators of their standing in the field.
The D-index threshold applied for identifying top researchers is calibrated in increments of 10, relative to the total estimated number of scholars within each discipline. This dynamic thresholding guarantees that the top 1% of leading scholars are incorporated in the listing. Furthermore, candidates for inclusion are expected to demonstrate a proximity of 30% or less between their overall H-index and their discipline-specific D-index, ensuring disciplinary impact is representative of their overall research profile.
Verification and Validation Practices
The Research.com team acknowledges that raw bibliometric data alone cannot serve as an absolute metric to evaluate the multifaceted output of scholars. In recognition of this, all scientist profiles featured in the ranking underwent meticulous manual verification. These profiles were cross-correlated against publications and records from a wide range of trustworthy and authoritative sources to confirm accuracy and authenticity.
While the number of papers published in prominent journals and conference proceedings is not a direct factor influencing a researcher’s position in the ranking, it remains a valuable secondary signal of a scientist’s scholarly contribution and engagement within Environmental Sciences.
The ranking positions are fundamentally established using each researcher’s D-index based on data from OpenAlex and CrossRef, which are among the most prominent and reputable bibliometric databases accessible to the global research community.
For comprehensive details regarding the methodology and processes involved in the creation of this ranking, we invite readers to visit our methodology page.
Research.com’s Commitment and Objectives
At Research.com, our mission is to inspire researchers, companies, and policymakers worldwide to examine the trajectories and achievements of leading experts across various scientific fields. By providing transparent and rigorously curated rankings, we aim to facilitate the scientific community’s understanding of who the foremost specialists are in specific research areas, within countries, or even at distinct research institutions.
Through this commitment, we strive to promote informed decision-making, foster collaboration, and highlight excellence in environmental sciences and beyond, contributing to the advancement of global scientific knowledge and innovation.