🔍 Key Concepts

• Diurnal inequality – what it means in terms of one high tide vs the other high tide in the same day • The difference between the Moon’s distance from Earth (perigee/apogee) and the Moon’s tilt relative to Earth’s equator (declination) • Which tidal characteristics are affected by gravitational strength vs. geometry/angle of the tide‑raising forces

💭 Think About

• Ask yourself: does diurnal inequality depend more on how strong the Moon’s pull is, or on the angle at which that pull acts relative to Earth’s equator? • Consider which options (perigee, apogee, weather, declination) would change the overall height of both tides together, and which would make one daily tide higher than the other. • Think about how often diurnal inequality patterns repeat: are they linked to short‑term weather systems, the Moon’s orbit distance cycle, or the slower change in the Moon’s position north/south of the equator?

✅ Before You Answer

• Be clear on the definition of perigee (Moon closest to Earth) and apogee (Moon farthest from Earth) and what they mainly affect. • Confirm that weather can cause irregularities in observed water levels but is it the primary cause of the regular pattern called diurnal inequality? • Identify which choice directly relates to the Moon’s north–south position relative to Earth’s equator, since that is tied to unequal daily tides.