I'm old enough that I remember switching between Yahoo, AskJeeves, AltaVista, and others, before abandoning them all for Google. I also remember experimenting with a friend to test the search engines, and I remember the question/query I used to perform the test: I had (at the time) a vague recollection that the level of the Atlantic and Pacific oceans near the Panama Canal is different; that in addition to raising ships over the isthmus, the canal has to raise them overall in one direction, and lower them in the other. That seems bizarre, since the oceans are connected south of South America, but that was my memory, so I asked the search engines. Google was the one engine that returned sites that confirmed my vague memory.

So of course, I just tried this with ChatGPT. It glitched mid-response, but here's the entire exchange:

Me: Is the level of the ocean the same on both sides of the Panama Canal?

ChatGPT: No, the ocean level is not the same on both sides of the Panama Canal. The Panama Canal is a man-made waterway that connects the Atlantic Ocean to the Pacific Ocean, and its locks raise and lower ships to accommodate differences in sea level between the two oceans.
-- Load failed -- I hit retry
The Atlantic Ocean side of the canal is higher than the Pacific Ocean side, with a difference in elevation of approximately 26 meters (85 feet). This difference in elevation is compensated for by a system of locks, which raise and lower ships to the appropriate level for transit through the canal. The locks fill with water from the higher ocean and drain into the lower ocean, allowing ships to pass from one ocean to the other without having to navigate significant differences in sea level.

Me: Why is the level of the ocean different?

ChatGPT: The difference in sea level between the Atlantic and Pacific sides of the Panama Canal is due to various geological and oceanographic factors.

One of the main reasons is the shape of the landmass and ocean basins. The Atlantic Ocean is relatively shallow and has a broader continental shelf, while the Pacific Ocean is deeper and has a narrower shelf. This shape influences the ocean currents and tides, and helps to maintain a difference in sea level between the two oceans.

Another factor is the prevailing winds and currents in the region. The trade winds in the Pacific and the prevailing westerlies in the Atlantic both play a role in shaping the sea levels on their respective sides of the canal.

Additionally, the location of the Panama Canal at the narrowest point of the Central American isthmus has a significant impact on the difference in sea level between the two oceans. The geography of the region funnels ocean currents and water into the narrow channel, leading to differences in water pressure and sea level on either side.

In summary, the difference in sea level between the Atlantic and Pacific sides of the Panama Canal is due to a combination of geological and oceanographic factors, including the shape of the landmass and ocean basins, prevailing winds and currents, and the geography of the region.

-- comment -- Although ChatGPT is correct that the levels differ, it is wrong about the amount: it's nowhere near 85 feet. It gives believable reasons for the difference, but doesn't mention tides, which (as I understand it) are a significant factor. It also doesn't mention salinity, which (again, as I understand it) is also a factor. I gave it a chance to catch the error:

Me: Is the difference really 85 feet?

ChatGPT: The difference in elevation between the Atlantic and Pacific sides of the Panama Canal is approximately 26 meters, or approximately 85 feet. However, it's worth noting that this figure can vary slightly due to tides, seasonal changes, and other factors. The exact difference in elevation can also depend on the specific location within the canal, as some areas may be slightly higher or lower than others. Nevertheless, the difference in elevation between the two sides is typically around 85 feet.

-- Comment -- No luck correcting that 85 feet number. I also asked about tides and salinity:

Me: Do tides or salinity contribute to the difference?

ChatGPT: Tides and salinity can contribute to the difference in sea level between the Atlantic and Pacific sides of the Panama Canal, but the main factor is the shape of the landmass and ocean basins, the prevailing winds and currents, and the geography of the region.

Tides do have an impact on the sea level in the canal, as they can cause fluctuations in the water level on both sides. However, the impact of tides on the difference in sea level between the two oceans is relatively small compared to the other factors mentioned above.

Salinity can also influence the sea level, as differences in salinity can cause water to expand or contract, leading to changes in sea level. However, the impact of salinity on the difference in sea level between the Atlantic and Pacific sides of the Panama Canal is also relatively small, as differences in salinity in the canal are primarily caused by fresh water inputs from rivers and rainfall, rather than differences in ocean salinity.

In summary, while tides and salinity can contribute to the difference in sea level in the Panama Canal, the main factor is the shape of the landmass and ocean basins, the prevailing winds and currents, and the geography of the region.

-- Comment -- Much has been made of ChatGPT's (sometimes unfounded) confidence. I don't know enough about the ocean-level subject to judge here. Clearly ChatGPT is confident, but is it correct? I don't know. Given that a quick Google search wasn't able to convince me that ChatGPT is wrong (apart from the 85 feet thing) I'm calling this even on the facts. The experience asking ChatGPT was clearly easier than Google.