Scientists say that doubling pre-industrial carbon dioxide levels will likely cause global average surface temperature to rise between 1.5Â° and 4.5Â° Celsius (2.7Â° to 8.1Â° Fahrenheit) compared to pre-industrial temperatures.
Furthermore, they may experience withdrawal symptoms that can include headaches and irritability, perceived loss of performance both physically and mentally. People suffering with intolerance to caffeine have reported feelings of disorientation, loss of judgment, anxiety, dizziness, agitation and a hyper activeness.
Symptoms of anxiety induced by the caffeine in coffee include nervousness, irritability, insomnia, jittery feelings and irregular or fast heartbeat.