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PORTLAND, Ore. (KOIN) – This lesson is for the Oregon and Washington coast kids! Today we are going to learn about “coastal upwelling” and the impact it has on the weather along the Oregon and Washington coast.
We have discussed the Pacific Ocean effect in many weather lessons because honestly, there is no way around it. Yet, we haven’t explored many of the direct actions of the Pacific Ocean. This lesson will discuss the relationship between our ocean water, wind and the coast.
This topic is fascinating for those of us that are inland or not living along the coast too. Why? Not only does this topic just pull you in like a good book, but it is useful for understanding meteorology and forecasting as a whole. So I must ask:
Have you heard of upwelling?
Well if you have heard of the term upwelling, it may have been used in the form of describing a group of people or an action that is taking over something, in other words, displaced. This is essentially the same concept, but it is related to water. This then has a direct consequence on the weather for some locations along the Oregon coast.
What exactly is upwelling?
Upwelling: The rising of water from below (colder) to the surface along coastlines where the wind at the surface has displaced the warmer surface water.
The diagram above is a general idea using a temperature gradient. It also gives an example of how this coastal upwelling works for our local coast. It is typically a consistent northerly wind that will influence this process. The water at the surface is warmer because of the sun. When the cooler sea surface temperatures take over these areas of the coast, it eventually leads to heat loss. That loss in heat changes the conditions for those beach communities that are close to those pockets. That cooler air will lead to marine clouds, and those clouds will then create a cooler environment. It can be a cycle that is tough to alter because of the temperature inversion in place. Meanwhile, areas inland are warm and sunny. Here is an example of this occurring on the Oregon coast, where temperatures around Newport were in the 50s and those communities that didn’t experience the upwelling, had temperatures around 70.
Upwelling for the Oregon coast is mostly prevalent during the summer months, but it also has an impact during the spring. Lastly, this water the water that is upwelling is a cool high–salinity, nutrient–rich water. This not only changes the weather for these locations, but it also has an impact on the ocean ecosystems for these communities!