Student protesters blocked the entrances to University Hall at Harvard University on Wednesday morning, demanding that school officials divest its endowment from the coal industry.

The protest is one of many efforts by students on campuses nationally, including an ongoing sit-in at the University of Pennsylvania, to force university endowments to stop investing in coal and other fossil fuels. Earlier this month, Columbia University’s president announced that trustees had voted, in keeping with the school’s commitment to addressing climate change, to divest from companies getting more than 35 percent of their revenue from thermal coal production.

For supporters, the movement gained urgency after President Trump’s actions on energy, the environment and climate change.

On Tuesday, Trump signed an executive order opening the door for companies to excavate fossil fuel on public land in the West. With coal miners at his side, Trump vowed to revitalize the industry and restore lost mining jobs, an action welcomed by many as a means to combat rural poverty and limit regulations.

But for Isa Flores-Jones, a sophomore from California studying history and literature at Harvard, the executive order added to her fears about climate change and the Trump administration. “That has added a lot of personal urgency for me about why I am out here and going to join the sit-in today.”

Given the size of Harvard’s endowment — more than $35 billion — investment decisions carry enormous weight.

A dozen protesters were stationed at doorways outside University Hall, a Bulfinch-designed symbolic center for Harvard. Flores-Jones said students were politely turning away people who tried to get to their offices, and they planned to remain there peacefully until 5 p.m. She said some students were willing to risk arrest.

In a letter to Harvard President Drew Faust, Divest Harvard called on the school to divest from the top 200 publicly traded fossil-fuel companies and asked it to start by divesting from any coal companies and pledging not to invest in them in the future. “Harvard must prioritize more than money and convenience; it must act morally and with a conscience.”

Flores-Jones said that the group had been told that the university has little to no investments in coal at this time but that they could not promise not to invest in it. The university’s continued investment in the fossil-fuel energy is an implicit encouragement of Trump’s agenda on energy, she said. “This is a political act.”

Harvard officials responded with a statement: “We agree that climate change is one of the world’s most urgent and serious issues, but we respectfully disagree with Divest Harvard on the means by which a university should confront it.

“Universities like Harvard have a crucial role to play in tackling climate change and Harvard is fully committed to leadership in this area through research, education, community engagement, and dramatically reducing its own carbon footprint.

“The University will continue to support its faculty, students and staff as they pursue a range of innovative and ambitious efforts to accelerate the world’s transition to renewable sources of energy and to help mitigate the potentially catastrophic consequences of climate change.”

In 2013, Faust wrote a letter on the issue to the campus community that included the idea that the university should “be very wary of steps intended to instrumentalize our endowment in ways that would appear to position the University as a political actor rather than an academic institution.

“Conceiving of the endowment not as an economic resource, but as a tool to inject the University into the political process or as a lever to exert economic pressure for social purposes, can entail serious risks to the independence of the academic enterprise. The endowment is a resource, not an instrument to impel social or political change.”

At Columbia, the university’s president, Lee Bollinger, said in a statement earlier this month, “Divestment of this type is an action the University takes only rarely and in service of our highest values. That is why there is a very careful and deliberative process leading up to any decision such as this. Clearly, we must do all we can as an institution to set a responsible course in this urgent area. I want to recognize the efforts of the many students, faculty and staff whose substantive contributions have brought us to this point.”

At the University of Pennsylvania, 10 students remained in College Hall on Wednesday morning in a continuing protest by the group Fossil Free Penn.

Amanda Mott, a spokeswoman for Penn, said the students’ latest demands — immediate divestment from coal and tar sands and full divestment from fossil fuel corporations within six months — had already been considered and answered.

“It was made clear to the students yesterday, as has been the case in the past, that the University would be happy to work with them to find additional ways to reduce Penn’s carbon footprint and lessen the need for fossil fuel use,” she wrote in an email.

“We are in agreement with them on the importance of this issue. We simply disagree on strategy: they are demanding that Penn divest, and the Trustees have already determined that fossil fuel does not meet the University’s criteria for divestment.”

An advisory committee reviewed the students’ proposal last year and concluded it did not meet the criteria for divestment, and in September, the executive committee of the trustees unanimously approved a resolution accepting an advisory committee’s recommendations not to divest from fossil fuels. The board feels strongly that they can have more influence on the issue through other steps, Mott said. “We are continuing to promote our sustainability initiatives, and are pursuing other avenues to engage productively and proactively on this important issue.”

Flores-Jones said Divest Harvard is working with student groups on other campuses, including several in Boston such as MIT and Northeastern University. At other schools, activists have been meeting with campus officials and targeting board members for phone calls and letters.