|Fig. 1 Glaciers in East Turkey (blue circle)|
I was fooled while trying to figure out the perplexing tide gauge history in the PSMSL database for the Black Sea area ("4.1 ft. of SLC ???").
A regular reader wondered about the precipitation records available, which would have an impact on outflow from the Danube, Dniestr, and other rivers flowing into the Black Sea.
I researched that issue then added to that post a Section V. concerning that issue.
But that did not solve some of the mystery and flux in the tide gauge record which caused me to keep pondering.
|Fig. 2 Georgia Glaciers (BlackSea)|
I hypothesized in my thinking that perhaps melting glaciers were feeding the major rivers that outflowed into the Black Sea.
Nope (read that post if you haven't yet).
Finally, it dawned on me that I had forgotten to consider ghost water (The Ghost-Water Constant, 2, 3, 4).
As it turns out, a number of countries have beaches along the Black Sea.
|Fig. 3 Caucus Mountains (Black Sea)|
This analysis is not completely solved, but the part of the puzzle that was right in front of my eyes (but I could not see it), led me to realize what others go through.
I should have known better, having read about ghost-water, having written about it, and having put forth a hypothesis about the magnitude of the influence of ghost-water, and of course after having seen proof of it (Proof of Concept - 3, Proof of Concept - 5).
Anyway, a lot of people have been, like me, the blind man in the group of blind men around the Elephant (The Warming Science Commentariat).
I am still on the case, pondering the various hinge lines (The Evolution and Migration of Sea Level Hinge Points) and gravity of this situation in the Black Sea (The Gravity of Sea Level Change, 2, 3, 4).
I just can't seem to get away from it.
A few examples of Black Sea glacial reality:
Kluhor (Klukhor) Glacier is in the Caucasus Mountains west of Mount Elbrus. It drains into the Teberda River and then the Kuban River and eventually Krasnodar Reservoir and the Black Sea. The Krasnodar Reservoir is primarily a flood control and irrigation management reservoir. Here we examine three glaciers each experiencing the familiar pattern in the Caucasus Mountains of retreat with expansion of proglacial lakes. As the area and number of glacier is reduced, the number and area of alpine lakes is increasing, note Khimsa Glacier, Georgia, Psysh Glaciers, Russia, and Gora Bashkara, Russia. Stokes et al (2006) note that 94% of Caucasus Mountain glaciers retreated from 1985 to 2000 and it is clear from the aforementioned that the trends continues. (AGU Blogosphere, emphasis added).The next post in this series is here, the previous post in this series is here.
Khimsa Glacier is a rare significant glacier south of the main crest of the Caucasus Mountains in Georgia. The glacier drains north to the Bzyb River, and then the Black Sea. The rivers upper reach is quite undeveloped and there is no hydropower along the river to date. The glacier flows from an elevation of 3000 m to 2650 m. In 1998 the glacier was 1.6 km long with a narrow terminus at the red arrow. At the transition to the glacier’s upper eastern slopes at Point A, there is only one small rock exposure. By 2013 the glacier has retreated 400 m to the yellow arrow, having lost 25% of its length in 15 years. The area of bedrock exposed on the upper eastern slope, at Point A, is significant now indicating thinning even high on the glacier. The glacier will soon separate near Point A into an upper and a lower section. In the Google Earth image the current terminus is indicated with orange dots and the glacier flow with blue arrows. Like Psysh Mountain glaciers 25 km north Khimsa Glacier thinning high on the glacier indicates it cannot survive current climate. Caucasus Mountain glaciers are in a period of rapid retreat (Shagedenova et al, 2009), that is attributed mainly to rising summer temperatures. Khimsa Glacier’s retreat parallels that of glaciers along the main crest of the Caucasus such as Kirtisho or Azau Glacier, though as a percent of total area lost it is greater. (AGU Blogosphere, emphasis added).
Changes in the area and number of glaciers in the Georgian Caucasus Mountains were examined over the last century, by comparing recent Landsat and ASTER images (2014) with older topographical maps (1911, 1960) along with middle and high mountain meteorological stations data. Total glacier area decreased by 8.1 ± 1.8 % (0.2 ± 0.04 % yr−1) or by 49.9 ± 10.6 km2 from 613.6 ± 9.8 km2 to 563.7 ± 11.3 km2 during 1911–1960, while the number of glaciers increased from 515 to 786. During 1960–2014, the total ice area decreased by 36.9 ± 2.2 % (0.7 ± 0.04 % yr−1) or by 207.9 ± 9.8 km2 from 563.7 ± 11.3 km2 to 355.8 ± 8.3 km2, while glacier numbers decreased from 786 to 637. In total, the area of Georgia glaciers reduced by 42.0 ± 2.0 % (0.4 ± 0.02 % yr−1) between 1911 and 2014. The eastern Caucasus section had the highest retreat rate of 67.3 ± 2.0 % (0.7 ± 0.02 % yr−1) over this period, while the central part of Georgian Caucasus had the lowest, 34.6 ± 1.8 % (0.3 ± 0.01 % yr−1), with the western Caucasus intermediate at 42.8 ± 2.7 % (0.4 ± 0.03 % yr−1). (Cryosphere).