Detailed Explanation:

In January (Northern Hemisphere winter), land cools much faster than oceans because land has a lower heat capacity. As a result, continents become much colder than nearby oceans at the same latitude. This temperature contrast causes isotherms to bend equatorward over land and poleward over oceans.

✅ Statement I is Correct: In January, isotherms dip southward over cold landmasses and curve northward over relatively warm oceans in the Northern Hemisphere.

✅ Statement II is Correct: Oceans retain heat longer than land, making oceanic areas warmer than continental areas during winter.

✅ Statement II explains Statement I: The temperature difference between colder land and warmer oceans is the direct reason for the bending of isotherms.

Short Notes: Isotherms

• Isotherms are lines joining places with equal temperature.

• In January, Northern Hemisphere continents are colder than oceans.

• Land heats and cools faster because it has lower specific heat than water.

• Oceans act as heat reservoirs and lose heat slowly.

• Isotherms bend equatorward over land and poleward over oceans in winter.

• In July, the pattern is generally reversed in the Northern Hemisphere.

• The greatest isotherm deviations occur over large landmasses such as Eurasia and North America.