Why Doesn’t the Yucatán Have Rivers?

The Yucatan Peninsula is a beautiful landscape with rich ecosystems, lush forests, and picturesque beaches, but it's missing something. Look at a map and you'll immediately notice it's lacking a feature that's pretty common nearly everywhere else on Earth. Major rivers. And it's not like the Yucatan is a desert. It rains over a,000 mm per year. That's about as damp as Seattle.

So, where does all the water go? Turns out it's hiding beneath our feet. The Yucatan is home to a network of underground tunnels thousands of kilometers long. This massive aquifer was partly carved by one of the most destructive events in our planet's history. And in turn, it has steered the course of life on the peninsula ever since.

Located mostly in Mexico, but also extending into Guatemala and Biz, the Yucatan Peninsula is made of a 1.5 kilometer thick block of limestone and other carbonate rocks. Carbonets are made from the remnants of marine life.

Lots of little shells and coral are compressed and eventually lithify into solid rock. This particular block began forming at the bottom of a shallow sea in the Triacic period over 200 million years ago and has continued to grow and evolve ever since. In fact, some of the limestones on the peninsula even formed in the last 10, 000 years. That's pretty much yesterday in geological terms.

But 66 million years ago at the end of the Cretaceous, something fairly dramatic

happened in the middle of the Yucatan. It's probably not news to you that a huge asteroid crashed into the Earth and ended the reign of the non-avian dinosaurs. Well, this is where it landed. So, is that the reason for the lack of major rivers today? Kind of yes, but mostly no. Let me explain. The main reason for the lack of rivers is all that limestone and a process that begins with the carbon dioxide in the atmosphere.