Doctor of Philosophy
PhDOverview
The doctoral program in Earth System Science at Stanford University prepares the next generation of scientists to tackle the world's most pressing environmental challenges through rigorous interdisciplinary training and cutting-edge research.
Earth System Science is the study of the world's air, water, land, and life as an integrated system. Our program unites basic and purpose-driven research to understand how the Earth functions, the many ways it is changing, and what the consequences of these changes will be for people and other species. We train students to understand, predict, and respond to human-caused and natural environmental change at local to global scales.
Doctoral students engage with fundamental Earth system science, from ocean circulation and biogeochemical cycles to climate dynamics, while also addressing critical sustainability challenges related to food, water, energy, biodiversity, climate change, and environmental justice. Our students study the food we eat, the water we drink, the air we breathe, and the plants and animals with which we share the planet, all while developing as independent researchers capable of making significant scientific contributions.
Requirements
Program Requirements
Distribution Requirements
Students must take one class from each of the following three areas within the first or second year
Area A: Analysis of the Earth System
Students must take one course to fulfill the Area A requirement. Alternative courses may be approved via petition.
BIO 231
Environmental Data Analysis
CS 229
Machine Learning
CS 230
Deep Learning
CEE 362A
Uncertainty Quantification
CME 204
Partial Differential Equations in Engineering
CME 215
Machine Learning and the Physical Sciences
DATASCI 294B
Data Science for Computational Molecular Biology
ENERGY 260
Uncertainty Quantification in Data-Centric Simulations
EPS 240
Data Science for Geoscience
GEP 268
Topics and Methods in Global Environmental Policy I
STATS 200
Introduction to Theoretical Statistics
STATS 202
Statistical Learning and Data Science
STATS 202F
Statistical Learning and Data Science [Flipped]
STATS 206
Applied Multivariate Analysis
STATS 207
Time Series Analysis
OCEANS 243H
Quantitative Methods for Marine Ecology and Conservation
Area B: Measurement of the Earth System
Students must take one course to fulfill the Area B requirement. Alternative courses may be approved by petition.
ESS 210
Techniques in Environmental Microbiology
ESS 224
Remote Sensing of Hydrology
ESS 241
Remote Sensing of the Oceans
ESS 259
Environmental Microbial Genomics
ESS 262
Remote Sensing of Land
EDUC 450C
Qualitative Interviewing
GEOPHYS 250
Fiber Sensing for a Sustainable Planet
OCEANS 306
Observational Methods in Coastal Oceanography
Area C: Earth System Processes, Models, and Human-Environmental Interactions
Students must take one course to fulfill the Area C requirement. Alternative courses may be approved via petition.
ESS 205
Fundamentals of Geobiology
ESS 206
World Food Economy
ESS 220
Physical Hydrogeology
ESS 223
Biosphere-Atmosphere Interactions
ESS 227
Decision Science for Environmental Threats
ESS 230
Pursuing Sustainability: Managing Complex Social Environmental Systems
ESS 244
Marine Ecosystem Modeling
ESS 246A
Atmosphere, Ocean, and Climate Dynamics: The Atmospheric Circulation
ESS 246B
Atmosphere, Ocean, and Climate Dynamics: the Ocean Circulation
ESS 247
Tropical Meteorology
ESS 258
Geomicrobiology
ESS 259
Environmental Microbial Genomics
ESS 267
Climate Change & Extreme Weather
Annual Review
Each year, the department evaluates students to assess progress to a degree, identify areas of strength, provide helpful resources, and note potential issues or areas of concern. This annual review includes a record of accomplishments presented by the student, written evaluations by the faculty advisor of the student’s progress, and (after the first year) committee feedback on the academic and research progress of the student. The student should have no ‘I’ grades in core courses, maintain a 3.0 grade-point average, and show evidence of productive and sustained research progress with no conflict of interest or commitment.
Possible outcomes of the annual review include:
Continuation of the student in good standing
Notifying the student that they are not making academic progress, with specific written guidelines for the necessary steps to reinstatement to good standing.
Annual reviews are required for all PhD students, including first-year PhD students. In the first year, the annual assessment is conducted between the student and the PhD advisor(s) (before forming a doctoral committee). After the first year, the annual review must be conducted between the student and the student’s doctoral committee. The committee should meet as a group simultaneously, although in the cases of extreme scheduling conflict a separate meeting can be organized with one of the committee members. In the unusual case where second-year PhD students have obtained approval for a delay in the qualifying exam, this annual review meeting should include a closed committee session. Post-candidacy review meetings typically last for one hour.
The student and advisor must complete and sign the written annual review form in all years. In the year students are undertaking their candidacy exam (research qualifying exam), that exam serves as the annual review. In addition, any student who has scheduled the dissertation defense and petitioned to graduate in Axess may elect not to hold an additional yearly review meeting.
Teaching Requirement
Teaching Assistantship
As a program requirement, students in ESS complete a minimum of two TA quarters. These should be the equivalent of a 25% position. In addition, additional TA quarters may be considered and/or required in consultation with the research advisor, depending on academic goals and funding availability.
Advancement to Candidacy
Candidacy Overivew
Admission to candidacy for the doctoral degree is a judgment by the faculty in the department or school of the student’s potential to successfully complete a Ph.D. It occurs when a student passes a qualifying exam and completes their required coursework. University policy is that admission to candidacy must normally occur by the end of the second year in the PhD program. Requests for extensions on this timeline must be provided in writing and approved by both the advisor and the Director of Graduate Students. They cannot be supported without sufficient cause (e.g., advisor on sabbatical). Scheduling constraints are generally not considered adequate cause.
The qualifying process consists of two components
Evaluation of a written document containing a proposal for the student’s PhD research
An oral examination
The first component, the research proposal, is a document whose text is up to – but no more than – 10 single-spaced pages in length (inclusive of figures, but exclusive of references, minimum 11 point font). It cannot include any supplementary text or appendices. The research proposal must concisely review the background literature and discuss the proposed problem, its importance, and the methods to be applied to the problem. The proposal must be well thought out, carefully written and edited, and finished with appropriate references and illustrations. It must be sent to the committee in final form at least two weeks before the date of the oral examination, and it must be reviewed by the advisor before being sent to the committee. Note that proposals that are longer than the maximum length can be sent back to the student for revision.
The second component, the qualifying examination, is a wide-ranging examination of the feasibility of the proposed research and the student’s preparedness to complete it. It starts with a presentation of no longer than 30 minutes, followed by a question and answer period, with questions from all committee members. These questions can cover the proposed research, the subfield in which it falls, and topics in which you should be proficient to conduct the research. The qualifying examination must be scheduled for at least 2.5 hours and for no more than 3 hours, although it may end earlier than the scheduled time. A 3 hour scheduling block is ideal, but this can be shortened to 2.5 hours in case of scheduling difficulties.
These two components (the written document and the qualifying examination) are judged by the student’s Examining Committee. The committee, including your faculty advisor or advisors, must consist of at least 4 and no more than 5 members, at least 3 of whom are academic council members at Stanford, and at least 2 of whom are appointed as faculty in the Department of Earth System Science. The committee must have a designated chair who is on the Academic Council, but who is not the student's dissertation research advisor(s). The chair’s Stanford appointment can be in either the Department of Earth System Science or a different Stanford department. The Examining Committee is typically, but not necessarily, the same as the university reading committee that evaluates the doctoral work. The outcome of the exam may be a ‘pass’, a ‘conditional pass’, a ‘retake’, or a ‘fail’. In the case of a conditional pass, a range of possible conditions can be imposed by the committee. In the case of a ‘retake’, the student is required to retake the exam in the next quarter (or if the exam is held in the spring quarter, this can be two quarters later). A student who received a ‘fail’ cannot continue in the program. However, if a student who failed the qualifying exam feels that the qualifying exam was performed in an unfair or inequitable manner, they may appeal to the department chair or Director of Graduate Studies (DGS) to request a new examination. Policies governing such appeals are described in the department handbook.
When evaluating the exam, the committee will assess the student's preparedness for completing the PhD along multiple axes:
Ability to synthesize existing literature and articulate both knowledge gaps and important outstanding questions.
Ability to communicate advanced topics clearly in writing and through verbal/visual displays.
Critical reasoning
Domain expertise
Feasibility of the proposed research and the student’s ability to conduct it
Oral Exam
University Oral Exam Overview
The doctoral dissertation is defended in the university oral examination.
Dissertation
Dissertation Overview
Under the supervision of the research advisory committee, the candidate must prepare a doctoral dissertation that is a contribution to knowledge and is the result of independent research. The format of the dissertation must meet university guidelines. The student is urged to prepare dissertation chapters that, in scientific content and format, are readily publishable.

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