Landscape Development and Climate Change in Southwest Bulgaria (Pirin Mountains)

Abstract

Tell me the past and I'll see the future. ConfuciusSoutheast Europe, the Balkans and not least the southwest Bulgarian Pirin region experienced an eventful natural and cultural history covering a time scale from millenia to the decades of the Younger Past, which has to be decrypted. Information on the Pirin mountains, stored in geo-archives, has been examined using modern methods and with great effort. This monograph seeks to summarize information on landscape and climate development in the region.For the Holocene period, the last 10,000 years or so, the forest and climate history of the mountain regions was reconstructed using pollen analysis of lake sediments and peat. The extensive work of Bulgarian colleagues was analyzed and supplemented with soil surveys.Our examination focused on an archive network in the Alpine timberline zone of the northern Pirins. This network provides tree-ring analyses of centuries-old soil and moraine investigations, firn and ice layers of recent glaciers, and culturalhistory inquiries, as well as analyses of relatively long-time climate data series. Thus, the climate, including its extremes, can be described in relatively high resolution, for the last 500 years.

The Unknown Southernmost Glaciers of Europe

“…Such analyses (isotope, radiocarbon, etc.) are costly and have been applied just for two of the small glaciers on the Balkan Peninsula (in Pirin [4][5][6] and Durmitor [24,25]). Absolute ages of surrounding moraines have been also retrieved by lichenometry for a glacier in Durmitor mountains [13].…”

“…The glacieret has an eastern exposure and a trapezoid shape with length of 80-100 m and width about 90 m. About 4-5 high moraine ridge surrounds glacieret body from three sides. It is considered to be formed in its present shape in the Little Ice Age [4][5][6] (Figure 3).…”

“…German scientists from Dresden measured glacieret area in the autumns of 1994, 1996 and 1998-2007. In 2006, they made three drillings of the firn, the deepest reaching the bottom at 11 m. Glacier ice with a density of 0.9 Kg/l was found in the cores at depths below 10 m, and the radiocarbon dating of organic particles from these depths confirmed the ice was at least 100 years old [4][5][6]. This is a direct evidence for the glacial nature of Snezhnika.…”

“…Small cirque glaciers have elongated contour, a longitudinal profile with a concave upper part and convex lower section of a tongue shape. Glacierets have simpler longitudinal cross-section (convex or concave or straight), lack of a pronounced tongue-like end and the width is often greater than length [4][5][6]. The presence of dynamic Glaciers Evolution in a Changing World downward motion of firn-ice mass has been, however, proved in both types [3].…”

“…On the Balkan Peninsula, the present existence of at least 16 small glaciers has been documented and studied in three of the highest mountains: Pirin (in Bulgaria), Prokletije (mainly in Albania) and Durmitor (in Montenegro) [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Some specific conditions combine to make them possible to exist 600-800 m below the present position of the climatic snow line (estimated between 2700 m in the Western Balkans and 3200 m in the Eastern Balkans, [12,19]): (1) altitudes between 1900 and 2600 m a. s. l. that provide for relatively low, annual, and seasonal air and ground temperatures (annual: +1 to +3°C, still too high for glaciers); (2) karstified carbonate bedrock, lightly coloured, with high albedo.…”