By Jason Klein
MES Graduate Maya Halma
Maya Halma is a 2026 graduate of the Master of Environmental Studies (MES) program at the University of Pennsylvania, where she concentrated in environmental sustainability. Before coming to Penn, she earned bachelor’s degrees in communication and social influence and Spanish from Temple University. She now works at the Water Center at Penn as a research and communication specialist.
For her capstone research, Maya worked with the Penn Center for Science, Sustainability, and the Media (PCSSM) to explore how socioeconomic status (SES) influences the effectiveness of behavioral interventions aimed at motivating climate action. Her study asked whether certain strategies work better for high SES individuals versus low SES individuals. She conducted an online experiment with about 800 participants who completed trivia quizzes designed to test two key drivers of behavior from the Theory of Planned Behavior: social norms and perceived ease.
Maya’s interest in this topic grew out of her undergraduate studies in communication, where she was first introduced to the Theory of Planned Behavior. She was drawn to applying this framework, traditionally used in health contexts, to climate behavior. With most Americans already believing in climate change but struggling to take meaningful action, Maya saw a critical gap that better communication strategies might help bridge. Her research seeks to uncover whether more targeted, audience-specific interventions could be the key to motivating sustained climate action.
Your research builds on an important challenge: many climate behavioral interventions fail to achieve sustained change. What was the main question you wanted to answer, and how did you go about testing it using the Theory of Planned Behavior?
I wanted to see if we should not be taking a one-size-fits-all approach to climate behavioral interventions. Maybe certain interventions are more effective for certain people. I started looking at socioeconomic status for a couple of reasons. First, it is a novel approach to the Theory of Planned Behavior, which gets into barriers and access but not necessarily socioeconomic status itself. Second, high socioeconomic status individuals contribute much more to the climate crisis than low SES individuals do. I wanted to see if there was a discrepancy in how motivated these groups could be and discover strategies that might be more effective for that specific demographic.
To test this, I used the Theory of Planned Behavior as my framework. This theory explains how humans are motivated to perform behaviors and identifies three key determinants: attitude, social norms, and perceived ease. I wanted to hold attitude constant and focus on the other two factors. For social norms, I tested specific behaviors rather than climate change in general. I looked at three behaviors: driving less, eating more vegetarian meals, and powering one’s home with renewable energy. I wanted to know, for example, if people think driving a gas vehicle is the norm, but maybe there are more EVs on the road than they think.
About the Framework: The Theory of Planned Behavior
The Theory of Planned Behavior, developed by Icek Ajzen, is a widely accepted psychological framework for understanding how people are motivated to perform specific behaviors. It proposes that an individual’s intention to perform a behavior is shaped by three key determinants:
- Attitude Toward the Behavior: A person’s positive or negative evaluation of performing the behavior. For example, do they view driving less as a good or bad thing?
- Subjective Norms (Social Norms): The perceived social pressure to perform or not perform the behavior. This includes beliefs about whether important people in one’s life or community approve of the behavior and whether the behavior is common among peers.
- Perceived Behavioral Control (Perceived Ease): The perceived ease or difficulty of performing the behavior. This accounts for factors like cost, time, effort, and access to resources needed to act.
The theory presumes that if a person has a favorable attitude, perceives social pressure to act, and believes the behavior is easy to do, they will have a stronger intention to perform the behavior. Intention, in turn, is the most direct predictor of actual behavior, assuming the person has the necessary opportunities and resources.
In Maya’s study, she focused specifically on social norms and perceived ease, holding attitude constant by only including participants who already believed in climate change. She designed trivia quizzes to test whether presenting new information about how common a behavior is (social norms) or how affordable and simple it is (perceived ease) could increase participants’ intention to engage in three climate-mitigating behaviors: driving less, eating more vegetarian meals, and using more renewable energy at home.
Study design: participants were divided into six conditions using a two (SES group) x three (trivia
quiz) design.
To test these drivers, we designed trivia quizzes with real statistics. For example, one question was: “Blank percent of Americans live within two miles of an EV charging station.” Participants had to guess the number, which was 60, and then rate how surprised they were. Participants were split into groups. Some received the social norms trivia quiz, some received the perceived ease quiz, and a control group received a fun facts quiz unrelated to the two drivers. Half of our sample was high SES, and half was low SES. Before the quiz, we asked how often they did each behavior. After the quiz, we asked how much they wanted to do the behavior in the future. We were looking to see if showing people this information moved the needle on their future intention.
You found that, overall, the interventions weren’t broadly effective. What was your reaction to that result, and what do you think it tells us about the difficulty of changing people’s minds on climate action?
It really shows that it is hard to change people’s minds. In our study, we controlled for things like political ideology, age, and gender because these factors are so potent. People’s identities play a huge role in how they act on climate. Overcoming that can be very difficult. Beliefs about social norms and ease may not be as strong as identity.
That being said, Allie Sinclair, a postdoctoral researcher at PCSSM, conducted a much larger study looking at a variety of climate behavior interventions. One of the interventions she tested was writing a letter to future generations. Participants wrote a letter about the environment and climate change, and what they hoped things would be like in 25 or 50 years. That intervention was very effective. So while my two interventions were not broadly effective, there are other creative strategies that can move the needle, and we need more research on them.
Despite that broad finding, you found a promising result regarding driving behavior. What did your study reveal about social norms and the choice to drive less?
We found that the social norms trivia quiz was marginally effective at getting people to drive less. Participants who received that intervention reported a greater future intention to drive gas or diesel vehicles less. This suggests people are particularly perceptive about social norms around driving. Maybe the information about how popular EVs are becoming was novel or interesting to them. We also found that the intervention was more effective for high SES participants than low SES participants. Individuals who were more educated and had higher income were more receptive to the social norms information and expressed greater intention to drive less in the future.
The concept of “prediction error” or accuracy on your trivia quiz was another key finding. Can you explain what that is and why it was a surprising but significant predictor of someone’s intention to act?
This was really interesting, and we are still analyzing it. My hypothesis was that the more surprising the information was, meaning the more inaccurate somebody was on the quiz, the more likely it would be to change their mind. New and surprising information should move people. But we found the opposite. People who were more accurate on the trivia quizzes, meaning they had a better understanding of how popular EVs are or how many people eat vegetarian meals, actually reported greater intention to do those behaviors.
There are a couple of possible explanations. One is that people who are more knowledgeable about climate change in general or about these specific behaviors might already be very prone to wanting to act. There is crossover between knowledge and intention. Another explanation could be confirmation bias. When people find out they were correct on the trivia quiz, it generates a positive feeling about the behavior and makes them want to do it more in the future. It was a counterintuitive result, but a significant one.
In simple terms, what is the single most important takeaway from your research for policymakers, communicators, or anyone trying to encourage climate-friendly behavior?
Broadly, my study suggests that social norms are the most salient belief in behavioral decision-making. People are most perceptive about social norms, and driving seems to be the easiest behavior to influence. For climate communicators and nonprofits, focusing on transportation could be really impactful. Tying driving less to social norms and making people realize that walking or taking public transportation might be more popular than they think could be effective.
Another big takeaway is that motivating action on climate change is just really difficult. We need to keep exploring different strategies, like the letter-writing exercise I mentioned. We cannot stop testing new approaches to see what works.
How did the MES program at Penn help you develop this research, and how did you involve other students or faculty in your work?
I actually knew before coming into the MES program that I wanted to work with PCSSM. I learned about them in an information session when I was applying. They are very connected to my research interests in environmental communication. I reached out to them once I had an abstract for my project, and they were willing to work with me.
I worked with Heather Kostick, the associate director, and Ovidia Stanoi, a postdoc at PCSSM. They were tremendously helpful. Since I planned to publish my study, there were a lot of extra hoops to jump through compared to a typical capstone project. There was extra documentation, and it was my first time being the lead author on an academic research study. I had to learn how to code, do all the data analysis, and apply for external funding. They helped me through all of that. Now we are editing the manuscript to submit for publication, and they are helping me make sure I am telling the right narrative and being detailed where I need to be. PCSSM also connected me with the Annenberg Public Policy Center, and they were all very helpful in the process.
What advice would you give to MES students who are just getting started on their capstone projects?
Start early, especially if you do not have an idea of what you want to do. My first semester, I started making a list of general topics I was interested in, and then I narrowed it down in the capstone seminar in the spring. Also, decide from the get-go if you want to publish. That is not a decision you can make once the project is done. There are many things you have to do along the way to get the project to the quality level needed for publication. Talk with your advisors about what additional things would be required and what the time commitment would look like. Understand that you will probably be working on it past the point of finishing the MES program.
The other thing is to budget much more time than you expect. I built in one or two extra months into my project, and I needed them. Some things took much longer than I thought, like tweaking the project plan for three to four months before we even got to data collection. Other things took much less time, like data collection, which I budgeted a month for but was done in five or six days. Definitely budget in extra time for delays.
Looking ahead, how will your MES program experience and capstone work advance you in your career?
Coming from a non-environmental background, the MES program really exposed me to a whole new realm, and I soaked everything up like a sponge. The professional master’s setup gave me a lot of real-world knowledge and experience I am using every day in my job at the Water Center, particularly from my water-focused courses.
My capstone was the first time I led an academic research project. I learned a lot from that experience, including hard skills like coding and applying for funding, but also soft skills like long-term project management and adaptability. I’m working on a handful of similar long-term research projects at the Water Center right now, and I’m using the same project management tools and tactics I used for my capstone.
Jason Klein is a Penn Climate student assistant who graduated from Penn’s MES program in May 2026.