But if you develop persistent muscle weakness, or muscle weakness with no apparent cause or normal explanation, it may be a sign of an underlying health problem. Voluntary muscle contractions are usually generated when your brain sends a signal through your spinal cord and nerves to a muscle.
Of these factors, only rising sea surface temperatures was found to influence hurricane intensity in a statistically significant way over a long-term basis. The other factors affected hurricane activity on short time scales only. rise in the world's sea surface temperatures was the primary contributor to the formation of stronger hurricanes since 1970, a new study reports.
Hurricanes only form over really warm ocean water of 80Â°F or warmer. The atmosphere (the air) must cool off very quickly the higher you go. Also, the wind must be blowing in the same direction and at the same speed to force air upward from the ocean surface.