1. The isotherms deviate to the north over the ocean and to the south over the continent.
2. The presence of cold ocean currents, Gulf Stream and North Atlantic Drift make the North Atlantic Ocean colder and the isotherms bend towards the north.
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Explanation
Isotherms are lines connecting places with equal temperatures. The horizontal distribution of temperature is depicted through isothermal maps, with the temperature reduced to sea level to eliminate altitude effects. Isotherms are generally parallel to the latitude. The deviation from this general trend is more pronounced in January than in July, especially in the northern hemisphere.
Statement 1 is correct: In January (winter in the Northern Hemisphere), continents lose heat quickly because land has a lower heat capacity than water. On the other hand, oceans retain heat longer due to their high heat capacity. As a result over continents (which are colder), isotherms shift southward, following the drop in temperature. While over oceans (which are warmer), isotherms shift northward, reflecting the retained warmth. This pattern is clearly visible on isothermal maps of the North Atlantic and Eurasian regions.
Statement 2 is incorrect: The Gulf Stream and the North Atlantic Drift are warm ocean currents, not cold. The Gulf Stream carries warm water from the Gulf of Mexico along the eastern coast of North America, while the North Atlantic Drift, an extension of the Gulf Stream, warms the western coasts of Europe. These warm currents increase temperatures in the North Atlantic region, making the area warmer, not colder. As a result, isotherms bend northward because the ocean is warmer than the surrounding continents, not due to cold currents. Fig.: Isotherms in January