Climate change is the reason for a lot of factors such as:
Heat-trapping Greenhouse Gases And The Earth's Climate
Greenhouse Gases
Reflectivity or Absorption of the Sun's Energy
Changes in the Earth's Orbit and Rotation
Variations in Solar Activity
Changes in the Earth's Reflectivity
Volcanic Activity
There's a lot more that I could list, but hopefully this will do.
Explanation:
In physical sciences, mechanical energy is the sum of potential energy and kinetic energy. It is the macroscopic energy associated with a system. The principle of conservation of mechanical energy states that if an isolated system is subject only to conservative forces, then the mechanical energy is constant. If an object moves in the opposite direction of a conservative net force, the potential energy will increase; and if the speed (not the velocity) of the object changes, the kinetic energy of the object also changes. In all real systems, however, nonconservative forces, such as frictional forces, will be present, but if they are of negligible magnitude, the mechanical energy changes little and its conservation is a useful approximation. In elastic collisions, the kinetic energy is conserved, but in inelastic collisions some mechanical energy may be converted into thermal energy. The equivalence between lost mechanical energy (dissipation) and an increase in temperature was discovered by James Prescott Joule.
Compared to coffee at room temperature, the molecules of the coffee at 34°C will be moving faster and colliding with one another more frequently.