Final answer:
Global warming is causing fish and other organisms to shift their distribution ranges, with freshwater and marine species moving towards poles or higher elevations. This also affects tropical species, leading to potential declines in biodiversity.
Step-by-step explanation:
Global warming affects the distribution ranges of organisms such as fish by altering their characteristic temperature ranges. As a result of climate change, cold-water species like trout are unable to survive in their current habitats. This is due to the ecosystems warming beyond their threshold for survival. Accordingly, other freshwater species and those in the marine environment are also facing distribution shifts, moving toward the poles or to higher elevations at a pace which is 12 times faster than terrestrial species.
Ocean temperature increases lead to shifts in marine populations and loss of habitats due to the rise in sea levels. Islands may reduce in size or disappear, affecting some species, and the freshwater cycle is jeopardized, causing potential overabundance of salt water.
Tropical species, especially those in lowlands, may face declines as upslope range shifts would be their primary means of survival when faced with increased warming. Predictions also highlight that global warming may cause significant biodiversity loss and that the rapid increase in temperature exceeds the rate at which species can adapt or migrate.