In studying Earth and its climate, we have only Earth itself as a model. By sending probes to other planets in the solar system scientists can gain more in-depth and useful information about planetary evolution. Venus, for instance, seems to have undergone a runaway global warming effect. We can use this information to help Earth's ever-growing climate change situation. By studying Venus, researchers might be able to better understand the processes which take place during a long period of planetary climate change. Those same researchers may be able to partner with engineers and environmentalists to better control and handle the climate crisis here on Earth.  Studying Mars, Earth's closest planetary neighbor, would allow an array of different types of scientists to apply the knowledge they find in the field to life on Earth. According to NASA, the main goal with a Mars exploration would be to discover whether or not humans can live for extended periods beyond low Earth orbit.  If something is in low Earth orbit, or LEO, then it is within 2000 km of the Earth's surface. Continuing to explore space and other planets within the solar system can allow scientists to better understand Earth, and make future predictions about climate change.
[P1] Exploring nearby planets would give us a deeper understanding of the Earth and the physical benefits or consequences of space exploration in general. [P2] Scientists can study other planets and use that information to better understand Earth.
Rejecting the premises
[Rejecting P1] Space exploration is such an exclusive field that the theoretical benefits of the practice itself would never really benefit humanity as a whole.