h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

14/01/2011

I have tried to post my thoughts to a couple of forums here at H2G2, whom I thought would give me some feedback to the feasabillity of my idea - to no avail; either the subject is outdated(it can't be) or I have addressed myself in the wrong forum for the topic(unlikely).
This is what I posted:
"
I think it is time for some experimental testing, instead of just all
these theories. I want to see some proof that the planet Earth is actually warming up.

I have an idea about a test that I believe could be performed, to prove that the temperature of the World's oceans (78% of the area of our planet), is actually getting warmer.

Here is how I believe this measurment can be achived: The density of water is related to temperature; And the speed of sound in water is related to the density of the water. Therefore I suggest that an international survey should be performed; By emitting a longwave signal through the waters of the Pacific Ocean, from the west coast of America to e.g New Zeeland or to the continent of Australia, and then measure the time taken for the the signal to travel over time.
"
I would be very interested in getting some feedback to this( Only related to the workings of physics, as we now it today, Please)

Thanks/Mikael

As mentioned in another thread, the experiment you propose would only tell us what temperature the ocean is the day the measurement is done. You would need to do it over a longer period of time, so see if the ocean temperature changes. That can of course be done as well, but might take decades. However there have been places on Earth where people have measured temperature constantly for centuries. In Prague there is a place called the Clementinum, where measurements of temperature has been done constantly for 250 years. Similar things have been done in other places, showing a general warming trend.