<span>Depletion of the ozone layer. Choloroflourocarbon (CFCS) are dangerous because of their destructive reaction with Ozone particles, which provide the Earth with a protective layer or shield against UV radiation. Depletion of the ozone layer begins when when CFC gets into the stratosphere. Sunlight breaks up cfcs releasing Chlorine Atom. Chlorine atoms in turn react with Ozone, starting a chemical cycle that destroys the ozone layer in that area. Once the ozone layer is depleted, there's nothing holding back the harmful UVB wavelengths of ultraviolet light (UV light) from passing through the Earth's atmosphere causing havoc on plants and animals.</span>
Answer:
Surface currents in the ocean are driven by global wind systems that are fueled by energy from the sun. Patterns of surface currents are determined by wind direction, Coriolis forces from the Earth's rotation, and the position of landforms that interact with the currents.
I believe the answer is: Different scientists use different data for investigation.
I say that because different scientists have different equipment, ideas, and have different methods. I hope I was right and i hope it helped and i wasn't to late to answer this question.