Atmospheric scientist and expert reviewer for the 2007 Nobel Peace Prize-winning Intergovernmental Panel on Climate Change, Katharine Hayhoe, gave the 2014 Edward Lamb Peace Lecture in the Union on Monday.

Hayhoe is the director of The Climate Science Center at Texas Tech University and is founder and CEO of ATMOS Research.

Her speech centered on a slideshow titled, “Years of Living Dangerously,” after a nine-part Showtime documentary television series. The series, by James Cameron, focuses on climate change and Hayhoe was interviewed for the project.

“Future change depends on choices now,” Hayhoe presented in her Powerpoint during the speech.

Hayhoe’s studies focus on climate change and she was named one of TIME’s 100 most influential people in the world for her promotion of action against climate change and her work toward improving the environment.

Senior Lindsay Fuller is an environmental studies major with a focus in policy and analysis. She said that she is receiving extra credit for attending the event, which prompted her to come, but that she would have come regardless given her interest and participation within environmental studies.

Environmental science major Makenzie Smith said that her teacher told her to attend the event.

“I am interested in the topic, so it’s relevant,” Smith said.

Hayhoe’s speech focused on a few popular questions with regards to climate change and those who are still skeptical on its existence and she began by stating these questions.

“How do we know it’s real? How do we know it’s because of human activities? What do we do about it?” Hayhoe said during the speech.

Hayhoe’s presentation was broken into four parts, each touching on the facts about climate change, the debunking of rumors and reasons that people should care about the changing climate.

Hayhoe said that ‘weather’ is used when referring week to week or day to day, but ‘climate’ is the long-term average of weather over at least 20-30 years.

This is why although the degree of severity in seasonal weather may change from year to year, these changes alone do not give credit or discredit global warming and climate change.

Hayhoe also spoke about the idea that people, especially within the western world, often act as though the climate will never change.

“Our civilization is built on the assumption of a stable climate,” Hayhoe said. “The problem is, it is changing.”

Senior Anna Vogelgesang is a music education major. She is taking an introduction to environmental studies class and said that the topic of climate change interests her.

“I’ve been trying to find ways to convince my friends that global warming exists,” Vogelgesang said.

She said having an expert share hard facts that support global warming reinforces her belief in the issue while also giving her information to share with others who are more skeptical.