Question:
I have been working on this fictional Northern Atlantic island for some time and would like help in determining the climate (koppen). I am thinking Cfa along the south/east coast and Cfb in the north/west. I am not sure about this because these climates rarely border each other in other parts of the world. I’m also unsure about the northeastern coast. For reference, the island spans from around 37 N to 44 N. Thanks for your help!
Answer:
For your fictional Northern Atlantic island spanning from 37°N to 44°N, a mix of Cfa (humid subtropical) and Cfb (oceanic) climates can be plausible with careful consideration of regional climate influences. Here’s how this might work and what factors to consider: Â
1. Climate Influences and Geographic Context
- Latitude: The island’s span from 37°N to 44°N places it in a temperate zone, similar to parts of the southeastern United States, the Iberian Peninsula, and southern Europe. The northern latitude range suggests cooler temperatures in the north and milder ones in the south.
- Oceanic Influence: Being in the Atlantic, the island would experience ocean/maritime effects, such as moderated temperatures year-round, higher humidity, and more consistent precipitation. The ocean’s influence could create conditions suitable for a Cfb climate, especially on the western and northern coasts, where prevailing winds often bring moisture.
2. Climate Border of Cfa and Cfb
- Cfa Climate (Humid Subtropical): Typically found in regions with warm to hot summers and mild winters, Cfa climates often have significant summer rainfall. For your island, this climate would fit well along the southeastern and southern coasts where warmer ocean currents could keep temperatures higher year-round.
- Cfb Climate (Oceanic): Characterized by cool summers and mild winters, with consistent rainfall throughout the year, Cfb climates are common in areas with strong maritime influences. This climate could be present on the western and northern coasts, where cooler ocean currents or prevailing winds from higher latitudes impact the temperatures.
3. Northeastern Coast Considerations
- Transitional Climate: The northeastern coast could have characteristics between Cfa and Cfb, perhaps leaning towards Cfb if exposed to cooler winds or ocean currents. If the area receives warm summer winds or lies in the path of a warmer current, it might also border on a warmer variation of the Cfb climate, such as Cfb/Cfa transition.
- Microclimates: Due to the island’s varied geography, you could include microclimates that depend on elevation or proximity to water bodies. For example, if there are any coastal highlands or upland areas, the climate could shift to Cfb even in the northeastern region.
4. Can Cfa and Cfb Border Each Other?
While it is rare, Cfa and Cfb climates can border each other, especially when there is a significant geographical feature or influence that creates a temperature and precipitation gradient. In your fictional world, this could be explained by:
- Mountain ranges or highlands separating the southern/eastern warm air from the cooler northern/western maritime air.
- Ocean currents: A warm current along the southeastern coast transitioning to a cooler current up north can cause adjacent but differing climates.
Conclusion and Recommendations
- Southern and Eastern Coasts: Cfa is feasible due to potential warm ocean currents and subtropical influences.
- Western and Northern Coasts: Cfb fits due to stronger maritime influence and cooler temperatures.
- Northeastern Coast: Could be a transition zone with cooler Cfb characteristics, or a Cfb/Cfa blend if it receives both cooler maritime air and warmer summer conditions.
