Associate Professor Sian Davies-Vollum writes from an around-the-world voyage through the Semester at Sea program.

At sea, somewhere between Morocco and Ghana—We are now at sea, into day six of our route from Casablanca, Morocco to Accra, Ghana. It has been absolutely fascinating to experience the changes in climate first hand as we have traveled from 30 degrees north of the equator to within a few degrees of the equator. We are so used to flying between places we don't appreciate the gradual shifts in temperature, humidity, winds and precipitation as we move between climate zones on Earth. I am so excited that I get to share all this with my students in the geography class that I am teaching! We arrive in Ghana the day after tomorrow; then we really will be in the tropics. I am bracing myself for heat and almost 100 percent humidity.

Learn more about Sian's trip around the world

Read all of Sian's Postcards dispatches.