Who led the expedition to the Arctic to document weather conditions?

The choice of Lt. Adolphus Greeley is correct because he was specifically known for his Arctic expeditions aimed at studying and documenting weather and environmental conditions in the region. His most notable expedition occurred from 1881 to 1884, during which he and his team gathered invaluable data about the Arctic climate.

Greeley's mission was part of a broader scientific effort during that era to explore and understand the Arctic, contributing significant insights into meteorological and geographic conditions. His expedition, which ultimately faced many challenges, focused heavily on the collection of scientific data, underscoring the nature of his leadership in advancing climatological knowledge.

In contrast, while Robert Peary, Ernest Shackleton, and John Franklin were all prominent figures in polar exploration, their aims were different. Peary is largely recognized for his efforts to reach the North Pole itself, Shackleton for his expeditions in the Antarctic, and Franklin for his tragic quest to navigate the Northwest Passage. Thus, Greeley's focused documentation of weather conditions distinguishes him as the appropriate choice for this question.