The process of osmosis accelerates when the temperature rises just as it does with any process of general diffusion. While the process of diffusion is more random than that of osmosis, both processes rely on the movement of particles to attain equilibrium. As a general rule, particles move faster when they are at elevated temperatures, and they move slower when at reduced temperatures.
Osmosis and diffusion are similar physical processes, and their reaction to an increase in temperatures is understandably similar. When two solutions are in contact with each other, the particles randomly move about both solutions, eventually attaining equal distribution of the two solutions. When this process is provided with more energy in the form of free heat, the molecules tend to move faster than before. This accelerates the process and makes the process of diffusion faster.
By contrast, osmosis is a type of diffusion that occurs across a semi-permeable membrane. However, as with diffusion, an increase in temperature accelerates the process. This has important implications for living organisms, especially those that live in widely fluctuating climates.
The rate of osmosis is generally measured in terms of osmotic pressure, but various authorities use different scales of reference. Osmotic pressure refers to the tendency of a solution to mix with less concentrated solutions.