Climate Change - what to expect for cruising life

[GordMay]

Originally Posted by Buzzman

... And to whoever asked about my solar PV, I have no idea of the actual voltage of the panels, but the inverter outputs 240VAC into our grid at 50Hz. It averages 16-20kW/h output per diem, averaged over a year. Can be double that on a daily basis, less in winter of course...

The Voltage is irrelevant, when you know the Wattage.
One kilowatt (1,000 Watts) is a unit of electric power, defined as the energy of 1,000 joules for 1 second.

A kilowatt hour (kWh) is a measure of how much energy you’re using, over time.


OOPS! I (now) see Stu beat me to it.

[SailOar]

Global Warming Might Be Making Waves Stronger

A new study published in the journal Nature Communications has revealed an as-yet-unseen consequence of climate change, wherein the energy of ocean waves have been increasing around the world caused by widespread ocean warming, which could potentially create further repercussions from coastal change and flooding, and the larger threat of sea level rise.

Published on January 14 in Nature Communications, the new study — “A recent increase in global wave power as a consequence of oceanic warming” — shows that global wave power (the transport of energy transferred from the wind into sea-surface motion) has increased around the world by 0.4% per year since 1948. The study also showed long-term correlations and statistical dependency with sea surface temperatures — both globally and by ocean sub-basins — and particularly between the tropical Atlantic temperatures and the wave power in high-south latitudes, already the most energetic region globally.

The results of the study show that upper-ocean warming — warming which is a direct consequence of anthropogenic global warming, as man’s excess warming is sunk into the ocean — is making waves stronger and identifies wave power as a potentially valuable, albeit unknown until now, climate change indicator.....

https://cleantechnica.com/2019/01/21/global-warming-might-be-making-waves-stronger/

[geoleo]

Originally Posted by DeepFrz

myocean, thanks for posting this but as you have already seen you wont get much useful discussion about climate change here.

Contrary to what has already been posted cruisers worldwide are already being affected by the stronger and longer lasting storms caused by climate change. The weather is less predictable and patterns are changing.

Increased poverty and damage to popular cruising destinations are going to make these places less desirable and more dangerous to visit.

That's funny- The UN has said that poverty worldwide has decreased dramatically worldwide in the past 50 years-especially in the ports of Asia who export lots to the USA!

[CatNewBee]

Originally Posted by SailOar

Global Warming Might Be Making Waves Stronger



https://cleantechnica.com/2019/01/21...aves-stronger/

Great for surfers!

Power is defined as mass * acceleration. Since there is no relativistic transition from mass in energy, because the ocean waves are far from speed of light, we can assume the difference mass of the water is neglectable when we are talking about temperature differences of some degree Kelvin. The acceleration is also not different in the same wind speeds, so there is not much more kinetic energy in a wave with 20°C water compared to the same wave (wave length, height, mass) with 23°C. BTW, when you warm up water it expands, so the mass decreases per volume and so does the kinetic energy of the impulse transferred per liter of water.

Of course it has more heat energy stored, but this is not directly transferable into motion energy of the wave.

That the ocean stores, transports and dissipates heat energy is nothing new btw.

[SailOar]

Originally Posted by CatNewBee

Great for surfers!

Power is defined as mass * acceleration. Since there is no relativistic transition from mass in energy, because the ocean waves are far from speed of light, we can assume the difference mass of the water is neglectable when we are talking about temperature differences of some degree Kelvin. The acceleration is also not different in the same wind speeds, so there is not much more kinetic energy in a wave with 20°C water compared to the same wave (wave length, height, mass) with 23°C. BTW, when you warm up water it expands, so the mass decreases per volume and so does the kinetic energy of the impulse transferred per liter of water.

Of course it has more heat energy stored, but this is not directly transferable into motion energy of the wave.

That the ocean stores, transports and dissipates heat energy is nothing new btw.

I'm not a physicist, but I assume that more powerful waves means bigger waves, not warmer waves.

[franksingleton]

Originally Posted by CatNewBee

Great for surfers!

Power is defined as mass * acceleration.

Unless my memory is adrift,

Force = mass * acceleration.

Power= force * velocity.

And
Kinetic Energy = 1/2 mass * velocity squared
Or
Potential Energy - mass * Gravity * height

[Reefmagnet]

Originally Posted by geoleo

That's funny- The UN has said that poverty worldwide has decreased dramatically worldwide in the past 50 years-especially in the ports of Asia who export lots to the USA!

Their describing the world after climate change's been "fixed".

[Alan Mighty]

Higher sea temperatures attributed to climate change cause fish (herring, in the case reported) and their predators (killer whales, in this case) towards the polar regions.

See: https://www.bangkokpost.com/news/wor...-migrate-north

[CatNewBee]

Waves are created by wind and the wave height is a function of water stream and slope on shore. Assuming the wind has not changed much, remains the slope. In deeper water the wave height is smaller and the waves built up when it gets quickly shallow.

Why should there be higher waves, when the water gets deeper by alleged rising sea levels ?

What I like on the article is, they claim some 0.4% increase of soething they cannot measure and have no idea where it comes from, nor understand the mechanisms behind, but know for sure it is "a direct consequence of anthropogenic global warming, as man’s excess warming is sunk into the ocean", because normal natural warming would probably not sink into the ocean, but stay at the surface .

Of course not man's excess warming. This makes huge waves, especially in some magazines and in discussions, that produce a lot of hot air.

Thank to the man's excess warming, waves are already become huge especially in tropical regions known to be dead flat and calm for centuries of sailing. What a finding!

This is just one of the many impacts that climate change is having upon the planet’s oceans and which have been observed for decades, if not longer.

Well this also a false claim, because the man made-up climate change hystery is not so old. And it is an impact of weather not of climate.

While alternatively impressive and distressing, these results are not just abstract changes but will have specific real-world implications for coastal cities and communities around the world.

City and community planners already need to understand and take into account the energy of ocean waves so as to properly build infrastructure — from ports and harbors, seaside residential dwelling, or breakwaters and levees.

Well, I wonder how the ancient people built their harbors and wave breakers without knowing this truth. They could never imagine waves and the power behind without this studies and were exposed un-sheltered to the nature's forces. It is so alternative impressing and distressing the same time! I would even call it "alternative facts"!

[AllenRbrts]

Originally Posted by CatNewBee

Great for surfers!

Power is defined as mass * acceleration. Since there is no relativistic transition from mass in energy, because the ocean waves are far from speed of light, we can assume the difference mass of the water is neglectable when we are talking about temperature differences of some degree Kelvin. The acceleration is also not different in the same wind speeds, so there is not much more kinetic energy in a wave with 20°C water compared to the same wave (wave length, height, mass) with 23°C. BTW, when you warm up water it expands, so the mass decreases per volume and so does the kinetic energy of the impulse transferred per liter of water.

Of course it has more heat energy stored, but this is not directly transferable into motion energy of the wave.

That the ocean stores, transports and dissipates heat energy is nothing new btw.

Perhaps it is better to read the actual paper and understand what is being discussed before speculating on what causes increased wave power. The causes are not that the waves have increased temperature, but that increase ocean temperatures are creating larger waves which are more powerful due to their size.

https://www.nature.com/articles/s41467-018-08066-0

[gonesail]

[SailOar]

Originally Posted by CatNewBee

.... It is so alternative impressing and distressing the same time! I would even call it "alternative facts"!

Given that your definition of POWER differs from the textbook definition of POWER, I'd guess that you have more experience with "alternative facts" than most.

[CatNewBee]

Originally Posted by Alan Mighty

Higher sea temperatures attributed to climate change cause fish (herring, in the case reported) and their predators (killer whales, in this case) towards the polar regions.

See: https://www.bangkokpost.com/news/wor...-migrate-north

This and the fishing industry, that almost extinct fish in some areas.
The predators follow the food as we know. If you are hungry and Mc D around the corner is closed, you'll migrate too to the next fast food restaurant.

In this case it is definitely man made, but it's not the warming.

[Lake-Effect]

Originally Posted by geoleo

That's funny- The UN has said that poverty worldwide has decreased dramatically worldwide in the past 50 years-especially in the ports of Asia who export lots to the USA!

Most Asian export ports are not cruising destinations, unless your taste runs to that sort of thing.

[CatNewBee]

Originally Posted by SailOar

Given that your definition of POWER differs from the textbook definition of POWER, I'd guess that you have more experience with "alternative facts" than most.

Kinetic Energy: wikipedia https://en.wikipedia.org/wiki/Kinetic_energy

see
Fluid dynamics
In fluid dynamics, the kinetic energy per unit volume at each point in an incompressible fluid flow field is called the dynamic pressure at that point


Power P = Delta E / Delta t where E is the energy and t is time. Because time is constant in our evaluation we can assume Energy is proportional to Power, and the dynamic energy of a wave is 0.5 * m * v² or m * a