It's a paradox: tourism plays a huge part in the destruction of the very environment that tourists trek so far to see.

Travel is embraced on global, national, and individual levels as it's as beneficial to economies as it is to the self. With air travel becomes more affordable than ever, the industry is thriving with no signs of slowing down.

The foot traffic, though, is getting to be too much for the environment.

Tourism's Huge Greenhouse Gas Emissions

In a study titled "The carbon footprint of global tourism," researchers led by Arunima Malik from the University of Sydney estimate that tourism is currently responsible for 8 percent of the world's greenhouse gas emissions.

The findings of this study are even more alarming with April reportedly hitting an all-time high in average carbon dioxide concentration in the atmosphere.

Malik's team included carbon dioxide and other types of greenhouse gases in the research, studying five years' worth of data from 2009 to 2013. The comprehensive study wasn't limited to greenhouse gas emissions from airplane trips and accommodations, but also included emissions coming from food and shopping items, among others.

Quartz reports that the direct and indirect emissions from tourism combine to almost 4.3 billion metric tons emitted annually. With more flights available than ever, a considerable chunk of the emissions can be traced to transportation, but food and shopping are also significant contributors.

Tourism's greenhouse gas emissions are found to be more exerted in and by high-income countries, although Quartz points out that the relationship between income and emissions are not quite linear. United States tops the list of contributors followed by China, Germany, India, and Mexico.

An Overwhelming Effect

There are attempts to curb tourism's negative impact on the environment, such as the development of more energy efficient practices and technology. However, the study notes, the demand for tourism is so high that the emissions are rapidly overtaking the decarbonization efforts of the industry.

"Right now, polluting is basically free," Dan Rutherford, program director of marine and aviation at the International Council on Clean Transportation, tells Mashable, adding that new fuel efficiency standards in new airplanes are getting overwhelmed by an increase in flying.

With air travel becoming so popular, carbon pollution is increasing as well.

"You've got these emissions in airspace, and countries don't want to claim them," Rutherford continues. "There is a kind of systematic denial going on."

The study is published in the journal Nature Climate Change.