698
Land-Ocean Systems in the Siberian Arctic: Dynamics and History
though they are based mainly on the bilateral Russian-German efforts under the projects
mentioned above.
Due to both the political change and the support from modem technology, the Laptev Sea as
well as its hinterland became only recently accessible to the international scientific community.
In close cooperation with the State Research Center - Arctic and Antarctic Research Institute
(AARI) in St. Petersburg (Russia), the GEOMAR Research Center for Marine Geosciences,
Kiel (Germany), originally carried out two land-based expeditions to the Laptev Sea. Both
expeditions, the Ameis '91 and the Esare '92 (Dethleff et al., 1993), were conducted during the
early spring of the respective years and focussed on the role of the shallow Laptev Sea shelf in
sediment entrainment into sea ice. These studies and furthermore the expeditions Transdrift I
aboard RV "Ivan Kireyev" to the inner Laptev Sea in 1993 (Kassens and Karpiy, 1994) and
Arctic 93 aboard RV "Polarstern" to the ice-covered continental slope of the Laptev Sea
(Fiitterer, 1994) revealed that the complex environmental system Laptev Sea required a
multidisciplinary approach as was realized within the scope of the research program devoted to
the "Laptev Sea System". These efforts were supplemented by the projects "Ecology of the
Marginal Seas of the Eurasian Arctic" and "Late Quaternary Environmental Evolution of Central
Taymyr". All these projects have been funded by the Russian and German Ministries of Science
and Technology.
In 1994, activities continued in the line of the Transdrift II expedition aboard RV "Professor
Multanovskiy" (Kassens et al., 1995a) and the first river expedition Lena 94 (Rachold et al.,
1995). The recovery of few long sediment cores from the inner Laptev Sea allowed
reconstructions of the paleoenvironment, i.e., changes in Lena River runoff. Contemporaneous
investigations on the Lena River itself contributed to the identification of the river's fingerprint
within the shelf deposits.
The expedition Transdrift III (1995) aboard the icebreaker "Kapitan Dranitsyn" met the most
difficult logistical demands, since research topics focused on processes which occur during the
extreme change from the ice-free conditions in late summer to the onset of freeze-up during
autumn (Kassens et al., 1997). This expedition was accompanied by both the RV "Polarstern"
ARK-XIII expedition (Rachor, 1997) and the land-based Lena-Yana expedition (Rachold et ai.,
1997a). RV "Polarstern" completed investigations during July to September 1995 within the
pack ice of the northernmost Laptev Sea, the adjacent deep-sea basin and on the Lomonosov
Ridge, thereby addressing relationships between shelf areas and adjacent deep-sea basins. The
river studies attempted to quantify the river's contribution to the sedimentary, chemical, and
hydrodynamic balance of the Laptev Sea (Rachold et al., 1996).
The primary objective of the Transdrift IV expediton was to study the Lena River break-up
and its influence on the environmental system of the Laptev Sea (Kassens et al., 1996). The
international biological Station "Lena-Nordenskiold", located in the eastern Lena Delta, was the
base for the scientists of the expedition. From here the field program in the Lena Delta and the
Laptev Sea was carried out. The river investigations were completed during the Khatangar 96
expedition in 1996 (Rachold et ai., in press).
All joint research activities were performed in a close formal cooperation between many
Russian and German scientific institutions (but with liaisons to many international programs
and institutions) and succeeded to draw a detailed picture of most important processes shaping
the Laptev Sea system (Figure 2). Beside national efforts, the multinational expedition
"Spaciba" (Martin et al., 1996) and the US-Russian expedition aboard the RV "Smirnitsky" in
1995 (Johnson, 1996) are the most important ones.
Land-Ocean Systems in the Siberian Arctic: Dynamics and History
though they are based mainly on the bilateral Russian-German efforts under the projects
mentioned above.
Due to both the political change and the support from modem technology, the Laptev Sea as
well as its hinterland became only recently accessible to the international scientific community.
In close cooperation with the State Research Center - Arctic and Antarctic Research Institute
(AARI) in St. Petersburg (Russia), the GEOMAR Research Center for Marine Geosciences,
Kiel (Germany), originally carried out two land-based expeditions to the Laptev Sea. Both
expeditions, the Ameis '91 and the Esare '92 (Dethleff et al., 1993), were conducted during the
early spring of the respective years and focussed on the role of the shallow Laptev Sea shelf in
sediment entrainment into sea ice. These studies and furthermore the expeditions Transdrift I
aboard RV "Ivan Kireyev" to the inner Laptev Sea in 1993 (Kassens and Karpiy, 1994) and
Arctic 93 aboard RV "Polarstern" to the ice-covered continental slope of the Laptev Sea
(Fiitterer, 1994) revealed that the complex environmental system Laptev Sea required a
multidisciplinary approach as was realized within the scope of the research program devoted to
the "Laptev Sea System". These efforts were supplemented by the projects "Ecology of the
Marginal Seas of the Eurasian Arctic" and "Late Quaternary Environmental Evolution of Central
Taymyr". All these projects have been funded by the Russian and German Ministries of Science
and Technology.
In 1994, activities continued in the line of the Transdrift II expedition aboard RV "Professor
Multanovskiy" (Kassens et al., 1995a) and the first river expedition Lena 94 (Rachold et al.,
1995). The recovery of few long sediment cores from the inner Laptev Sea allowed
reconstructions of the paleoenvironment, i.e., changes in Lena River runoff. Contemporaneous
investigations on the Lena River itself contributed to the identification of the river's fingerprint
within the shelf deposits.
The expedition Transdrift III (1995) aboard the icebreaker "Kapitan Dranitsyn" met the most
difficult logistical demands, since research topics focused on processes which occur during the
extreme change from the ice-free conditions in late summer to the onset of freeze-up during
autumn (Kassens et al., 1997). This expedition was accompanied by both the RV "Polarstern"
ARK-XIII expedition (Rachor, 1997) and the land-based Lena-Yana expedition (Rachold et ai.,
1997a). RV "Polarstern" completed investigations during July to September 1995 within the
pack ice of the northernmost Laptev Sea, the adjacent deep-sea basin and on the Lomonosov
Ridge, thereby addressing relationships between shelf areas and adjacent deep-sea basins. The
river studies attempted to quantify the river's contribution to the sedimentary, chemical, and
hydrodynamic balance of the Laptev Sea (Rachold et al., 1996).
The primary objective of the Transdrift IV expediton was to study the Lena River break-up
and its influence on the environmental system of the Laptev Sea (Kassens et al., 1996). The
international biological Station "Lena-Nordenskiold", located in the eastern Lena Delta, was the
base for the scientists of the expedition. From here the field program in the Lena Delta and the
Laptev Sea was carried out. The river investigations were completed during the Khatangar 96
expedition in 1996 (Rachold et ai., in press).
All joint research activities were performed in a close formal cooperation between many
Russian and German scientific institutions (but with liaisons to many international programs
and institutions) and succeeded to draw a detailed picture of most important processes shaping
the Laptev Sea system (Figure 2). Beside national efforts, the multinational expedition
"Spaciba" (Martin et al., 1996) and the US-Russian expedition aboard the RV "Smirnitsky" in
1995 (Johnson, 1996) are the most important ones.