Moist air from coasts exists thanks to warm oceanic currents. These currents might change even in current geography so that even despite average temperature ris

Moist air from coasts exists thanks to warm oceanic currents. These currents might change even in current geography so that even despite average temperature rises, the currents move farther from areas suitable for agriculture. Or, on the other hand, the water becomes hotter and produce strong hurricanes/typhoons more regularly. Neither is good for crops.