For 10 points, name these events, which, when sufficiently strong, develop a convection-free zone called the eye.
An inverse relation between the frequencies of these events in two locations is explained by the Madden-Julian oscillation. Their size is measured by the ROCI, or radius of outermost closed isobar. One structure frequently associated with these events results in the "stadium effect" and undergoes replacement cycles, which scientists have attempted to induce to (*) weaken these events. These events have paths that enter "recurvature" when the begin moving poleward and eastward, many of which pass up the Atlantic coast, and they are classified on the Saffir-Simpson scale. For 10 points, name these events, which, when sufficiently strong, develop a convection-free zone called the eye.
An inverse relation between the frequencies of these events in two locations is explained by the Madden-Julian oscillation.
{hurricanes} [or {typhoons}; or {tropical storms}; or {cyclonic storms}; or {tropical depressions}; or {cyclones}]