Within the next few hundred years, Venice, Italy could become a diver’s dream, Australia’s Great Barrier Reef may lose hundreds of species of marine life, and ancient glaciers could shrink to the size of ice cubes. Why? Many of Earth’s natural and man-made wonders are disappearing because of climate change and pollution.

As summer break draws nearer and nearer, some of us may begin thinking about destinations for vacation, but some of Earth’s wonders—both natural and man made—are disappearing at a spectacular rate. Common causes for the loss of these amazing locations around the globe include rising temperatures and pollution.

Venice, Italy

Venice, Italy is made up of millions of wooden piles sitting on 118 islands composed of unstable silt. 1,500 years after it was built, the ancient city is now in danger of being submerged lost to the Adriatic Sea.

A few factors contribute to Venice’s sinking. The first is the settling of the loose sediment the city is built on. This sediment comes from the Po and Piave Rivers and was built upon by Venice’s original settlers. The founders of Venice were Italian refugees escaping from invaders. They used the natural maze of canals to keep out intruders and over time, the city began to grow and thrive. Now, it is a tourist hotspot, bringing in around 50,000 tourists every day.

Other causes for Venice’s sinking are man-made structures and projects. New buildings like railroad bridges and piers have altered the sea floor and tidal cycles, making the city more vulnerable to flooding. Twentieth century groundwater pumping has made matters worse, bringing water from natural aquifers under the city to the surface. As a result, Venice has sunk nine inches in the last century and spurred protective efforts by the local government.

Australia’s Great Barrier Reef

The Great Barrier Reef is the size of 70 million football fields and includes 3,000 coral reefs, 600 islands, and thousands of species of marine life. As with Venice, there are multiple problems plaguing the Great Barrier Reef. In recent years, Australia has suffered from powerful cyclones. These cyclones, especially those in 2010 and 2011, caused extensive damage to the structure of the reef and flooded areas of the mainland. As the floodwater receded into the ocean, it brought with it pollutants that raised the salinity of the water, which can sicken and kill marine life. Adding to the problem is climate change, which has raised oceans’ acidity and temperature. Because the increased levels of carbon dioxide generated by human activity are absorbed into Earth’s oceans, the reef has suffered from higher levels of acidity. Many organisms in the Great Barrier Reef cannot live in water with higher acidity than they are used to, leading to coral bleaching, or the loss of necessary algae from coral, and lowered reef growth. Increased temperatures affect the Great Barrier Reef in similar ways to ocean acidification; when marine organisms are exposed to non-optimal temperatures, they become unhealthy and may die. According to the Great Barrier Reef Marine Park Authority, ocean temperatures may rise more than 30 degrees in the next century.

According to CNN, the combined effects of ocean acidification, rising temperatures, and powerful cyclones may facilitate tremendous loss of life in the Great Barrier Reef within the next few decades.

Glacier National Park, Montana

In 1850, Glacier National Park contained about 150 glaciers. When the region became a national park in 1910, about the same number of glaciers remained. In 2010, 160 years later, fewer than 25 full-size glaciers remained. The ones that still exist are constantly shrinking, and the largest may be gone by 2030.

Glaciers are large chunks of ice and snow that slowly move, picking up rocks and boulders as they go. They form over time as snowfall exceeds the amount of ice melting, and the glaciers in Glacier National Park formed about 7,000 years ago. In the last few decades, however, Glacier National Park has experienced warmer temperatures and less snowpack, or snow that maintains the size of the glaciers. These factors combined lead to the gradual shrinking of glaciers, until they disappear. But who cares if the glaciers shrink?

Well, not only do glaciers bring in tourists, but, according to the Northern Rocky Mountain Science Center, “Glaciers act as a ‘bank’ of water (stored as ice) whose continual melt helps regulate stream temperatures and maintains streamflow during late summer and drought periods when other sources are depleted. Without glacial melt-water, summer water temperatures will increase and may cause the local extinction of temperature-sensitive aquatic species, disrupting the basis of the aquatic food chain.” In short, the disappearance of glaciers could spur a domino effect significant enough to destroy local ecosystems.

Venice, the Great Barrier Reef, and Glacier National Park are not the only wonders of the world threatened by climate change and pollution. Many species of plants and animals are threatened or endangered and many island countries face rising sea levels. Only time will tell if human efforts to preserve Earth’s treasures will be successful but, just in case, book your flights now!