Complex sentence: He also developed a mathematical model comparing variations in solar radiation across the Earth's surface, which was later used by scientists Wladimir Köppen and Alfred Wegener to deduce past climates over drifting continents.
Split into simpler sentences: He also developed a mathematical model comparing variations in solar radiation across the Earth's surface. This was later used by scientists Wladimir Köppen and Alfred Wegener to deduce past climates over drifting continents.