The other side of sea level change:

[GordMay]

The Other Side of Sea Level Change:

In many parts of the world, sea levels are rising, due to global warming.
But, scientists note that warming, and increased evaporation, are likely to play out differently for inland seas and lakes.

In the case of the Caspian Sea [technically a lake], scientists anticipate rapid declines in water levels in the coming decades and centuries.
Radar altimetry data, collected by multiple satellites, and compiled by NASA's Global Water Monitor, indicate that the Caspian's water levels have already been dropping, since the mid-1990s.

By one estimate [1], Caspian water levels could drop by 9 to 18 meters [30 to 59 feet], by the end of the 21st century, enough that it would lose about a quarter of its area, and uncover about 93,000 square kilometers [36,000 square miles] of dry land. That is an area about as large as Portugal.

Research [1], published in Nature’s journal Communications Earth & Environment, reveals that, depending on global emissions scenarios, the Caspian could fall by up to 18 meters by the end of the century.

The shrinking sea isn’t the result of human water diversion alone, as was the case with the Aral Sea.

More about:
"One of the World’s Largest Seas Is Disappearing Before Our Eyes—Shrinking 30CM Every Year With No Signs of Slowing” ~ by Arezki Amiri
➥ https://www.msn.com/en-ca/weather/to...39203b9a&ei=35

The study:
[1] “Climate-driven 21st century Caspian Sea level decline estimated from CMIP6 projections” ~ by Rohit Samant & Matthias Prange
➥ https://www.nature.com/articles/s43247-023-01017-8

[barnakiel]

A world is a process. While we might like to prefer no change (we are not wired to cope well with changes) the fact of life is that change is the only constant.


Take my good lady wife as an example. La donna e mobile. Et j'aime ça.


Unlike many, I do like the fact that the sea levels are rising. Here (Atlantic) they change twice a day and the change is between 5 and 9 feet - daily. So when I hear 1/2 of an inch per 100 years is big drama I say eh.


I remember Aral was just one big lake that have disappeared. There was also a major place somewhere in the US with boats and piers there and it is all gone. But such places make awesome photo shoot backgrounds today. We lose some we win some.


May there be changes.


barnakiel

[SailOar]

Originally Posted by barnakiel

... So when I hear 1/2 of an inch per 100 years is big drama I say eh....
barnakiel

IF ONLY the rate of sea level rise were 1/2" per hundred years! The rate in 2024 was 23" per 100 years, and is expected to accelerate.

https://sealevel.nasa.gov/news/282/n...-rise-in-2024/

[GordMay]

Originally Posted by SailOar

IF ONLY the rate of sea level rise were 1/2" per hundred years! The rate in 2024 was 23" per 100 years, and is expected to accelerate.

https://sealevel.nasa.gov/news/282/n...-rise-in-2024/

Indeed.
According to NOAA*, the rate of global sea level rise is accelerating. It has more than doubled, from 0.06 inches [1.4 millimeters] per year, throughout most of the twentieth century, to 0.14 inches [3.6 millimeters] per year, from 2006–2015.
By the end of the century, global mean sea level is likely to rise at least one foot (0.3 meters) above 2000 levels, even if greenhouse gas emissions follow a relatively low pathway in coming decades.
The global average sea level has risen 8–9 inches [21–24 cm] since 1880 [to 2023].

* ➥ https://www.climate.gov/news-feature...obal-sea-level
* ➥ https://www.star.nesdis.noaa.gov/socd/lsa/SeaLevelRise/

[SailOar]

Human impact on the ocean will double by 2050

Our cumulative impact on the oceans, which is already substantial, is going to double by 2050 — in just 25 years,” said marine ecologist and NCEAS director Ben Halpern[...]

Their quest to build a comprehensive model of human impacts on the ocean led to a 2008 paper in the journal Science, a landmark study that synthesized 17 global data sets to map the intensity and extent of human activity on the world’s oceans. That initial view revealed startling results: No place was untouched, and 41% of the world’s marine environments were heavily impacted.

“The previous paper tells us where we are; the current paper tells us where we are headed,” Halpern said[...]

Ocean warming and biomass loss due to fisheries are expected to be the largest overall contributors to future cumulative impacts. Meanwhile, the tropics face rapidly increasing rates of impact, while the poles, which already experience a high level of impact, are expected to experience even more. According to the paper, the high level of future impacts “may exceed the capacity of ecosystems to cope with environmental change,” in turn posing challenges for human societies and institutions in a variety of ways.”

The world’s coasts are expected to bear the brunt of these increasing cumulative impacts — an unsurprising reality, the researchers say, given most human uses of the ocean are near coasts. Yet it’s also a “worrisome result nonetheless,” according to the paper, because the coasts “are where people derive most value from the ocean.” Additionally, many countries are dependent on the ocean for food, livelihood and other benefits. “Many of these countries will face substantial increases,” Halpern said[...]

[boatpoker]

Change is guid Donkey - Shrek

[GordMay]

Originally Posted by boatpoker

Change is guid Donkey - Shrek

“Change is Good Donkey!” ~ by Angela Gravelle
➥ https://www.linkedin.com/pulse/chang...ngela-gravelle

“So change isn’t easy – who said it was?

Too often we see people who say they are committed to change but at the first instant that arises which demonstrates their level of commitment it is clear they have been “faking the change”. All along they have been paying lip service without any real commitment to supporting the actions required to implement the change. ...”

[boatpoker]

Originally Posted by GordMay

“Change is Good Donkey!” ~ by Angela Gravelle
➥ https://www.linkedin.com/pulse/chang...ngela-gravelle

"Good" simply does not carry the weight without the Scottish accent of
"Guid"

[barnakiel]

Originally Posted by SailOar

IF ONLY the rate of sea level rise were 1/2" per hundred years! The rate in 2024 was 23" per 100 years, and is expected to accelerate.

https://sealevel.nasa.gov/news/282/n...-rise-in-2024/

But, my dear, year 2024 was only one year. So how did you resolve for a whole 100 years' period?


Well. If predicting future were THAT simple, then we all would have been Bitcoin billionaires long ago!


Somehow, we are not.


"Past performance is not a reliable indicator of future performance”. The government (ASIC) requires businesses to state this disclaimer whenever past data is used to make projections about expected future profits. Yet somehow, scientists are never required to post such a statement whenever they make their overly dramatic statements about the future of the planet!


Buyer beware. Do not buy all they are saying.


:-)
barnakiel

[aberglas]

In 100 years time, I doubt the robots will care.


But will they want to go sailing?


When Computers Can Think

[Chotu]

and here I was thinking that you were going to talk about the positive side. More anchorages for us! Ha ha ha

[GordMay]

Originally Posted by barnakiel

But, my dear, year 2024 was only one year. So how did you resolve for a whole 100 years' period?
...

"Past performance is not a reliable indicator of future performance”. The government (ASIC) requires businesses to state this disclaimer whenever past data is used to make projections about expected future profits. Yet somehow, scientists are never required to post such a statement whenever they make their overly dramatic statements about the future of the planet!

Buyer beware. Do not buy all they are saying.
:-)
barnakiel

One way to think about it is darts. While looking at the last dart, to predict the next one, is obviously a fool’s errand, studying the complete track record, of the thrower, is an excellent way to understand the likely range of future outcomes.
While the accuracy of a player’s last toss may not tell you much, about her next toss; the accuracy of her last 100, will be a reasonable predictor, of her next 100.

Hindcasting [a historical re-forecast of ‘past performance’] is fundamental to the development of computer [climate] models.

Hindcasting [‘past performance’] proves a theory [physics-based model of ‘future performance’], by testing if a predictive model can accurately simulate past events, for which data already exists.
By running a model, with past conditions, to see if it matches historical observations, scientists validate its ability to explain [forecast] phenomena, like climate trends, or economic cycles.
A model that accurately reproduces past conditions, is considered more reliable, for predicting future events, and supporting the underlying theory it was built upon.

So, steer clear of the cynicism, that traps you in a nihilistic belief, that past performance is irrelevant, and nobody knows nuttin’.

[GordMay]

I should have pointed out that, organizations, like the World Meteorological Organization and the U.S. National Weather Service use 30-year periods, for their official climate averages.
Climate trends are identified by comparing successive 30-year averages.
Even with slight year-to-year variations, a 30-year timeframe shows the consistent direction of change, indicating a real trend.

According to NASA Science*, and other experts, for determining climate trends, a minimum period of 30 years is standard, for calculating climate averages, known as climate normals, which are updated each decade.
While individual years, and shorter periods, show year-to-year variations, this 30-year baseline helps distinguish long-term trends, from short-term fluctuations, enabling the detection of shifts in temperature and other climate patterns.

Recent rates of global warming [1994-2024] are larger, than the longer-term average rates [1901-2024], indicating an upward trend in warming.

*“What Is Climate Change?” ~ by NASA
➥ https://science.nasa.gov/climate-cha...20or%20decades.

Originally Posted by NASA

“... Weather refers to atmospheric conditions that occur locally over short periods of time—from minutes to hours or days. Familiar examples include rain, snow, clouds, winds, floods, or thunderstorms.

Climate, on the other hand, refers to the long-term (usually at least 30 years) regional or even global average of temperature, humidity, and rainfall patterns over seasons, years, or decades. ...”

“Climate change: global temperature” ~ by Rebecca Lindsey, & LuAnn Dahlman, for NOAA Climate.gov
➥ https://www.climate.gov/news-feature...al-temperature
[quote] “... Earth’s temperature has risen by an average of 0.11° Fahrenheit (0.06° Celsius) per decade since 1850, or about 2° F in total.
The rate of warming since 1982 is more than three times as fast: 0.36° F (0.20° C) per decade... [


Sea Level Change Portal
NASA's portal for an in-depth look at the science behind sea level change.
➥ https://sealevel.nasa.gov/

[barnakiel]

Originally Posted by GordMay

One way to think about it is darts. While looking at the last dart, to predict the next one, is obviously a fool’s errand, studying the complete track record, of the thrower, is an excellent way to understand the likely range of future outcomes.
While the accuracy of a player’s last toss may not tell you much, about her next toss; the accuracy of her last 100, will be a reasonable predictor, of her next 100.

Hindcasting [a historical re-forecast of ‘past performance’] is fundamental to the development of computer [climate] models.

Hindcasting [‘past performance’] proves a theory [physics-based model of ‘future performance’], by testing if a predictive model can accurately simulate past events, for which data already exists.
By running a model, with past conditions, to see if it matches historical observations, scientists validate its ability to explain [forecast] phenomena, like climate trends, or economic cycles.
A model that accurately reproduces past conditions, is considered more reliable, for predicting future events, and supporting the underlying theory it was built upon.

So, steer clear of the cynicism, that traps you in a nihilistic belief, that past performance is irrelevant, and nobody knows nuttin’.

Yes. True.


Think of it: 1+1 is 2 (true) and 2*1 is 2 (true). Clearly then, many things, many statements, can be true at once. That you are right does not imply I am wrong.


Cynicism? I am not sure. It is just a label. Makes pointing out a target easy. So that the rest of the mad crowd can go for them and get them.


You may accidentally remember, some time back Northern Europe was covered with glaciers. And at a point too the Med was just a salty shallow pool and people used to live there some 20 meters below sea level. See how it all REVERSED. Big surprise. Carrots in Stockholm and their caves deep under the sea level. Today.


etc


What I am saying is that a trend obvious today may go flat tomorrow and reverse next week. A trend is a fact. Its duration unknown, and its reversal certain. Nature likes changes. And nature likes to change changes too. CHANGE in fact is nature. Think of evolution - would you really prefer to still be a monkey? And yet. Here we are. Proud of not being monkeys. God bless the change.


Today / tomorrow / next week - measured in God's days.


We are looking for patterns where there are none. Because we are looking for order. Because order makes us feel safe.


But the world is NOT ordered. It is a human concept, the ORDER. Just like LOVE and GOD and CLIMATE CHANGE.


One can be objective and superstitious all at once. There is no shame in this. But it is good to see it for what it is. The human condition.

https://www.youtube.com/watch?v=0CFuCYNx-1g

+love+peace+truth,
barnakiel

[GordMay]

Originally Posted by barnakiel

... many things, many statements, can be true at once. That you are right does not imply I am wrong. ...
barnakiel

I was not trying to prove that you [“Past performance is not a reliable indicator of future performance”] were wrong - just that your comment was [more or less] irrelevant.


The linked article, “Climate change: global temperature” ~ by Rebecca Lindsey, & LuAnn Dahlman, describes the longer climate trends [“So how did you resolve for a whole 100 years' period?”]

The scientific study of climate science is a feedback loop, where theory and observation work together.
When observed trends, match a physics-based model's predictions, it strengthens confidence in the underlying physics theories. Discrepancies drive new research, to improve models, and understanding.

So, the observed climate trends are not a matter of belief, but are the physical manifestations of well-understood physical laws, demonstrating the accuracy of physics-based climate theories.

Other scientific evidence, from ice cores, tree rings, and ocean sediments further corroborates these theories, by showing that current warming is occurring at an unprecedented rate, compared to past natural warming periods.

The current warming rate is significantly faster, than average warming rates, after past ice ages, a trend that aligns with the rapid increase of human-caused greenhouse gases.