competitive relationship or altering other processes such as carbon sequestration. In Europe, the temperature and precipitation effects due to climate change can indirectly affect certain populations of people. The rise of temperatures and lack of precipitation results in different river floodplains, which reduce the populations of people sensitive to flood risk. Climate change can have an impact on medicinal plants by altering the environmental conditions of where they grow, to the point where the conditions are no longer ideal and habitable. The range of a symbiotic fungi associated with plant roots (i.e., mycorrhizae) may directly change as a result of altered climate, resulting in a change in the plant's distribution. A new grass may spread into a region, altering the fire regime and greatly changing the species composition. A pathogen or parasite may change its interactions with a plant, such as a pathogenic fungus becoming more common in an area where rainfall increases. Increased temperatures may allow herbivores to expand further into alpine regions, significantly impacting the composition of alpine herbfields. Coupled natural and human systems work as systems that influence change over broad spatial and temporal extents that are usually seen as indirect effects of climate change. This is especially true when analyzing spillover systems. Environmental factor#Socioeconomic Drivers Higher level changes Species respond in very different ways to climate change. Variation in the distribution, phenology and abundance of species will lead to inevitable changes in the relative abundance of species and their interactions. These changes will flow on to affect the structure and function of ecosystems. Bird migration patterns are already showing a change in flying south sooner, and returning sooner, this could over time affect the overall ecosystem. If birds are leaving sooner this would decrease the pollination rates of some plants over time. The observation of bird migrations is more evidence of the climate changing, which would result in plants flowering at different times. With certain species of plants having a disadvantage with a warmer climate, their insect herbivores may also be taking a hit. Temperature will directly affect diversity, persistence and survival in both the plants and their insect herbivores. As these insect herbivores decrease, so will the higher levels of species that eat those insects. This cascading event would be detrimental to our earth and how we view nature today. Challenges of modeling future impacts Accurate predictions of the future impacts of climate change on