Oscar Wilde said that “Conversation about the weather is the last refuge of the unimaginative.”
Sorry Oscar, despite my deep respect and admiration to you I will have to object this one.
Talking about the weather is lame; I seriously thought before. But I have changed my mind, since I moved to the Oregon Coast. Talking about the weather is lame at the cases that the weather is consistent, predictable and largely warm and sunny. This is not the case at the Pacific Northwest.
I often find myself complaining about the weather (this is my version of talking about it) since I moved here, and now it’s time to better look into it. Without my usual pout when I curse the rain, or my frown when it’s sunny but really windy. I am not grumpy in reality; I am just a bicycle commuter. That means that I don’t have the choice of a well heated, or at least a dry seat at bike-unfriendly times. I am always exposed to the weather and it affects me every single day. I have been repeatedly soaked by the North Pacific rain and blown away by the Northerly winds (we name the winds from the direction that they come from) over and over again. Immediately when I arrived here I was warned about the horizontal rain that I had never heard of before and no umbrella could keep it off me. The wind is ruthless at the North Pacific.
The truth is that everyone is affected by the weather and has his/her own relationship with it depending on where they come from, what they are used too and how their internal thermostat is tuned, and also on their personality. If you come from Greece, the Oregon Coast will appear cold, whereas if you come from northern France (clear reference to one of my housemates) it will feel like home. If you are outgoing and social the warm sunny weather suits you and defines you. If you are more of an introvert the rain and the low temperatures will provide the right conditions for you to stay home and enjoy solitude.
Research shows that the weather and particularly the sun affect our mood. I clearly see more smiley faces in a sunny day, mine included. Studies indicate a link between low pressure and suicide. On rainy days people report lower satisfaction with their lives. Now imagine how challenging it can be to be a graduate student in a tiny town on the Oregon Coast…!
Overall, I think that the amount of energy that we receive from the huge flaming star on the sky defines who we are, and seems to be a driver of peoples cultures. I am certain that you also have noticed generic cultural differences among people that come from southern and northern regions in a global or even in a national scale. I might be judged for stereotyping but there is some truth to that.
There are 3 major factors why the weather is important for biologists-acousticians:
1. It is linked to food and everyone cares about food
The animals care about the weather! Their distribution is defined by the climate together with other parameters. The sperm whales for example, being truly cosmopolitan, are encountered in the most parts of the world’s seas from the equator to the edge of the polar ice. However they have their temperature preferences. The females like it warm and don’t go to temperatures lower than 15°C. While the groups of females and young males are thought to remain in lower latitudes year round, the macho adult males have wider physiological demands and are encountered in polar areas.
The sperm whales display a remarkable sexual dimorphism with the males being ~1.5 times longer than the females. The larger the size of the animal the more favorable is the surface-to-volume ratio. Even though they have a large surface area that they lose heat from, this area is small in relation to their heat-producing body mass. Thus the males can migrate to high latitudes, especially during summer months, to productive feeding grounds where they karaoke with my hydrophone located at the Gulf of Alaska.
Within their calls I am sure that whales talk about the weather too because highly productive spots are identified, like upwelling areas and other cool places where plenty of food is available and the animals tend to aggregate. Though, the precise process that links the environmental factors in the open ocean with the distribution and abundance of large predators is difficult to be determined and is a major goal of my research. Investigating the oceanographic parameters that affect the movements of sperm whale populations is a particularly complicated matter since they feed on deep sea creatures (bathypelagic squid) and the linkages of physical forcing (wind, temperature) with primary productivity and aggregations of prey and predators are temporally and spatially variable.
2. The sound in the ocean likes it hot
The propagation of sound in the oceans is largely affected by oceanographic variables (which are related to the weather) such as temperature, pressure and salinity. The speed that the sound travels underwater varies from area to area, season to season and different time in the day. Generally the sound speed increases when all the above variables increase. Since these variables change with the depth, the sound speed profile also changes with depth in the water column.
High sound velocity on the sea surface where the water gets warmed up by the sunlight decreases down to the depth where the water temperature becomes constant (~1000m) and then it starts increasing again when the pressure increase is dominant. At the transition point where the sound velocity reaches a minimum (~1000m) it is formed a sound channel where sound waves get trapped and propagate really far away. This is named as the SOFAR (SOund Fixing And Ranging) Channel and some species of whales find it to be very useful to communicate with their friends, partners, parents, cousins and aunts that are immigrants to faraway seas.
I use skype.
Do remember this SOFAR chitchat when you decide to deploy your instrument to record whale voices and you cannot decide on the depth 😉
And to turn the talk-about-the-weather into a hot topic, consider what happens when climate change is introduced and the small talk becomes a conversation where personal ethics, political and social opinions are involved. More like loud talk now! Now that I said loud, did you wonder what is the effect of climate change to the sound propagation and consequently the whales’ communication, and you were afraid to ask?
Ocean acidification, the decrease of the pH in the seas, is a notorious climate change impact. This increase of the ocean acidity changes how sound travels underwater: the lower the pH (more acidic), the ocean absorbs less sound and the higher is the sound speed. And now you are thinking: “Voila, the whales can be heard even further now!”. However, the reality is less comforting (as usually). At the frequencies that the whales vocalize we make a whole lot of noise with shipping and naval activity, seismic exploration and other significant anthropogenic sound sources that interfere with the whales’ skype and consequent communication issues. Yep, ocean acidification makes the sound pollution in the seas into a magnified problem.
3. People love listening to the rain
Since the weather affects the ocean soundscape, then it can also be measured by the sound it makes! Rain and wind generate sound at the sea by producing bubbles during splashing at the ocean surface. These physical processes create different distribution of bubble sizes that have a different footprint on the soundscape. This way the sound from breaking waves (caused by the wind) can be distinguished from the rainfall sound and we are able to monitor the ocean surface conditions from below the surface. Huzzah, here is the solution to trying to measure wind speed and precipitation in difficult locations where the measured vicious weather elements can actually destroy the instruments that we use to measure them. The instrument that I use, the Passive Aquatic Listener (aka PAL) was originally designed by Dr. Jeffrey Nystuen to detect and measure rainfall and wind speed at sea. Lucky me, it works great with recording marine mammals too!
Weather and bubbles talk. This is so scientific.
By this point of this post I have been unnecessarily negative with the Oregon Coast weather which to be frank is what makes this corner of the world into a magical place. The northerly winds in the summer are the reason for the upwelling to take place and all the whales and other astounding marine life to move up this way for food. Seeing the whales from the beach or even just the balcony of your house is certainly worth suffering some cold winds. The world we live in is alive because of the winds. The wind is the breath and the heartbeat of the Earth. The rain on the other hand gives life to thriving and fairytale-like old-growth forests with splendidly diverse and abundant wildlife, fills the rivers and the lakes. Did I mention how outdoorsy I have become?
A question to you: do you also see an irony in the name “Pacific” or I am being grumpy again?
Here it comes, a welcome wind: the wind of change. I am moving to the valley!