As long as we're mentioning minor nits

I enjoyed the OZ stories when a kid, but couldn't swallow flying monkeys even before learning about the square/cube ratio.

Just starting HFQ. Near when Green Valley is musing about the cold weather equipment there is a casual mention of the north's "short winter twilight." As a North Dakotan, I can testify that the days are short, but the sun tends to almost peek over the horizon for quite a time. Consider the poles, with twilights lasting for months!

Looking forward to finishing HFQ!

My pet peve is an HFQ where we have an island 40 miles long with no reliable water!

Unless it is literally a 40 mile long string less than 200 yards wide an island that size will have good perminant water supplies. A normal island shaped island in this size is larger than most of the carribean islands or the scotish islands all of which have perminant water.

Silverwall wrote:My pet peve is an HFQ where we have an island 40 miles long with no reliable water!

Unless it is literally a 40 mile long string less than 200 yards wide an island that size will have good perminant water supplies. A normal island shaped island in this size is larger than most of the carribean islands or the scotish islands all of which have perminant water.

Maybe every practically accessible bit of it ends up in bogs or brackish marshes, and no small part of it isn't even that accessible? Granted, I got the impression it was instead a whole heaping lot of mere dry rock and sand, but there could be other ways to get a non-tiny island without significant accessible fresh water.

JeffEngel wrote:

Silverwall wrote:My pet peve is an HFQ where we have an island 40 miles long with no reliable water!

Unless it is literally a 40 mile long string less than 200 yards wide an island that size will have good perminant water supplies. A normal island shaped island in this size is larger than most of the carribean islands or the scotish islands all of which have perminant water.

Maybe every practically accessible bit of it ends up in bogs or brackish marshes, and no small part of it isn't even that accessible? Granted, I got the impression it was instead a whole heaping lot of mere dry rock and sand, but there could be other ways to get a non-tiny island without significant accessible fresh water.

There are dozens of islands that have little or no fresh water. IIRC it was a reliable source of water.

JeffEngel wrote:

Silverwall wrote:My pet peve is an HFQ where we have an island 40 miles long with no reliable water!

Unless it is literally a 40 mile long string less than 200 yards wide an island that size will have good perminant water supplies. A normal island shaped island in this size is larger than most of the carribean islands or the scotish islands all of which have perminant water.

Maybe every practically accessible bit of it ends up in bogs or brackish marshes, and no small part of it isn't even that accessible? Granted, I got the impression it was instead a whole heaping lot of mere dry rock and sand, but there could be other ways to get a non-tiny island without significant accessible fresh water.

Only if it rains. It may have the climate of the Atacama desert or the costs of the Persian gulf. It may then be bare volcanic rock, all run off, no soak in.

In our world only very very small islands (Less than 1-2 square miles or so) have no fresh water and once you get over 10 square miles they all have reliable fresh water. Despite what hollywood would have you believe an actual desert island is an impossibility because of the cooling effect of the oceans keeping the temperature lower. Also if it is that hot you will get rain daily because of how thunderstorms are the mechanism that prevents tropical temps getting totally out of controll in oceanic settings. It is the lack of water inland that allows deserts such as the arabian peninsula to form, even the the coast is quite livable in the main because of the cooling effect of the oceans.

a 40 mile long island is much much bigger than small pacific island nations such as Tuvalu https://en.wikipedia.org/wiki/Tuvalu#Ge ... nmentwhich has a total area in 4-5 islands of only about 10 square miles total but still supports 10,000 population but at a significant water pressure on fresh water lenses in the coral islands https://en.wikipedia.org/wiki/Tuvalu#Wa ... sanitation

A good analogy for a cold climate island is the main island of the shetlands group https://en.wikipedia.org/wiki/Mainland,_Shetland which has an area of 374 square miles and the smaller islands at the same latitude all have reliable water supplies until we get to the very small ones.

What all this shows is that a 40 mile long axis island is so far beyond the size of perminant fresh water it's not funny. If the island was only 2-3 miles long axis then there might be more of a case.

I am ignoring arctic and subantarctic climates as the island in question is stated as being in the gulf of dholar. As an asside the gulf of Dholar represents a body of water at least as large as our mediterranean sea as far as I can tell from the given dimensions of close to 2000 miles long axis.

Silverwall wrote:In our world only very very small islands (Less than 1-2 square miles or so) have no fresh water and once you get over 10 square miles they all have reliable fresh water. Despite what hollywood would have you believe an actual desert island is an impossibility because of the cooling effect of the oceans keeping the temperature lower. Also if it is that hot you will get rain daily because of how thunderstorms are the mechanism that prevents tropical temps getting totally out of controll in oceanic settings. It is the lack of water inland that allows deserts such as the arabian peninsula to form, even the the coast is quite livable in the main because of the cooling effect of the oceans.

a 40 mile long island is much much bigger than small pacific island nations such as Tuvalu https://en.wikipedia.org/wiki/Tuvalu#Ge ... nmentwhich has a total area in 4-5 islands of only about 10 square miles total but still supports 10,000 population but at a significant water pressure on fresh water lenses in the coral islands https://en.wikipedia.org/wiki/Tuvalu#Wa ... sanitation

A good analogy for a cold climate island is the main island of the shetlands group https://en.wikipedia.org/wiki/Mainland,_Shetland which has an area of 374 square miles and the smaller islands at the same latitude all have reliable water supplies until we get to the very small ones.

What all this shows is that a 40 mile long axis island is so far beyond the size of perminant fresh water it's not funny. If the island was only 2-3 miles long axis then there might be more of a case.

I am ignoring arctic and subantarctic climates as the island in question is stated as being in the gulf of dholar. As an asside the gulf of Dholar represents a body of water at least as large as our mediterranean sea as far as I can tell from the given dimensions of close to 2000 miles long axis.

First of all,there is Espanola island also known as Hood island in the Galapagos. It has an area of 23 sq. miles (60 sq. kms. for the civilized among us)and no fresh water. In fact the mockingbirds drink sea lion urine to get fresh water.

Second, lower temps over the ocean would lead to winds that flow from the island to the ocean. Once the hot air from the island cools and releases it's moisture, the precipitation would be over water.

For an island to affect the precipitation over it the topography needs to be high enough to force prevailing winds up high enough to cool off and release moisture over the island. That requires mountains. This is known as 'orographic rainfall'.

Low lying islands like Espanola are incapable of doing this and are reliant on precipitation that would have fallen anyway. If the island has little or no natural catchment basins, the precipitation will simply run off without creating any pools or lakes.

For an island to have groundwater reserves, the bedrock has to have limited porosity. The water flows too quickly through porous rocks to remain for any length of time but without at least a little porosity, no water seeps into the rocks.

Finally, the island in the book was never described as having no water supply, only limited. In both cases Charis brought a small fleet of ships. That would means at least several thousand more people. A water supply adequate for a few hundred people would be inadequate in that situation.

Bermuda is notorious for relying on rainwater catchments because it has no rivers, lakes, or other reliable sources of fresh water.

Cheers

John

"In our world ..."

Safehold is *not* our world!
Not only can the author impose conditions of his choosing with
a movement of his pen (in this case with a world to his voice-
recognition software), but he provided that it would be altered
by professional 23rd century terraformers to the specific
conditions he desires for his story.

And, if by some odd chance all of *that* does not suffice,
then he simply *lies* about. ("All novelists are liars.")

If you can't tolerate reading lies,
if nothing but provable truth will do for you,
Then go thou and read Euclid!

Howard True Map-addict (my pen-name, not my birth names)

Silverwall wrote:In our world only very very small islands (Less than 1-2 square miles or so) have no fresh water and once you get over 10 square miles they all have reliable fresh water.

{snip - htm}

Easternmystic wrote:First of all,there is Espanola island also known as Hood island in the Galapagos. It has an area of 23 sq. miles (60 sq. kms. for the civilized among us)and no fresh water. In fact the mockingbirds drink sea lion urine to get fresh water.

Second, lower temps over the ocean would lead to winds that flow from the island to the ocean. Once the hot air from the island cools and releases it's moisture, the precipitation would be over water.

For an island to affect the precipitation over it the topography needs to be high enough to force prevailing winds up high enough to cool off and release moisture over the island. That requires mountains. This is known as 'orographic rainfall'.

Low lying islands like Espanola are incapable of doing this and are reliant on precipitation that would have fallen anyway. If the island has little or no natural catchment basins, the precipitation will simply run off without creating any pools or lakes.

For an island to have groundwater reserves, the bedrock has to have limited porosity. The water flows too quickly through porous rocks to remain for any length of time but without at least a little porosity, no water seeps into the rocks.

Finally, the island in the book was never described as having no water supply, only limited. In both cases Charis brought a small fleet of ships. That would means at least several thousand more people. A water supply adequate for a few hundred people would be inadequate in that situation.

Actually, on not-very-large islands limited porosity isnt necessary, sand or other high porosity underground will do just fine.
In contrast to bigger land masses, the water cannot seep away on a small island because the ocean guarantees a certain level of ground water.
Salt water is heavier than drinking water, so a bubble of drinking water will float on the salty ground water from the surrounding ocean, forming a layer that can be tapped by wells.
Lack of porosity remains a problem, and lack of rain makes the entire question moot.