African dust from the Sahara desert is observed across the Atlantic as far west as the Caribbean region where it produces a hazy sky condition during the annual dry season. You are a climate scientist and make a prediction that the Sahara was not a desert during glacial periods in the northern hemisphere. How could you test this hypothesis by looking at deep sea sediments from the Atlantic off west Africa?

Question

Quizplus · Accepted Answer

By looking at the sediments, you could see if there are biogenic sediments (indicating a wetter climate with more organisms present) that are interbedded with sediments that have terrigeneous input (indicating a drier climate with more dust). This would allow you to identify intervals of dry, interglacial periods when the Sahara may not have been a desert. Measuring isotopes in the sediment could provide additional information about temperature changes, but would not necessarily address the question of desertification. Looking at fossils, while potentially informative, may not directly address the question at hand.

African Dust from the Sahara Desert Is Observed Across the Atlantic