Na 1 Nachlass Max Horkheimer, 36 - Korrespondenzen u.a. mit Karl Menninger vom The Menninger Clinic, The Menninger Sanatorium, Topeka, Kansas (p. I 18, 188-334)

15 Brief zwischen Heinrich Meng und Max Horkheimer sowie Briefwechsel mit The Johns Hopkins Hospital, Baltimore Maryland, 1935-1940; 4 Briefe zwischen dem The Johns Hopkins Hospital, Baltimore, Maryland und Max Horkheimer, 1940; 1 Brief von Werner Münsterberger an Max Horkheimer, 13.03.1940; 44 Briefe zwischen Karl Menninger vom The Menninger Clinic, The Menninger Sanatorium, Topeka, Kansas und Max Horkheimer, 1938-1941;

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 334 - Nachdrückliche Bitte an Professor Hugo von Meltzl der anonymisierten Autorenschaft bei seinen Artikeln

u.a.: Ferdinand Laban;

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 371 - Persönliche Anmerkungen an den Kieler Professor der Chirurgie Luois Stromeyer zum beiderseitigen Verhältnis

u.a.: Adele Schopenhauer;

Na 1 Nachlass Max Horkheimer, 371 - Korrespondenzen u.a. mit Franz Neumann (p. V 128, 178-268)

20 Briefe zwischen dem Studenten Iwan Nagel und Max Horkheimer, 1952-1953; 20 Briefe und Beilage zwischen Theodor W. Adorno sowie Max Horkheimer und Iwan Nagel, 1952-1953; Material "Gegen N. aus der NS-Zeit" von Professor Hans Naujoks an Max Horkheimer, 1954; 3 Briefe zwischen dem Professor John U.Nef und Max Horkheimer, 1953; 7 Briefe zwischen der Studentin Dorothee Neff und Max Horkheimer, 1951-1956; 3 Briefe an den Historiker und Sozialwissenschaftler Benjamin Nelson von Max Horkheimer, 1959; 31 Briefe und Beilage zwischen dem Professor Franz L. Neumann und Max Horkheimer, 1950-1954;

Ms.Ff.F.Stoltze 3. 334 - Brief von Friedrich Stoltze an Else Bußler

Neujahrsglückwünsche (Gedicht), Einladung nach Frankfurt

Ms.Ff.F.Stoltze 3. 371 - Brief von Friedrich Stoltze an Feodor Körber

Frankfurter Latern, Holzstöcke, Satzanweisungen

Na 1 Nachlass Max Horkheimer, 586 - Korrespondenzen mit Friedrich (Frederick) Pollock (p. VI 36, 110-334)

1 Brief von Frederick Pollock an Walter Munding, 16.08.1950; 1 Brief von Frederick Pollock an Joseph Christ, 24.05.1950; 1 Brief von Albert Flegenheimer an Frederick Pollock, 18.05.1950; 2 Briefe von Frederick Pollock an E. Wehrle, 03.04.1950; 1 Brief von Margot von Mendelssohn an Max Horkheimer, 18.01.1950; 1 Brief von Nothern Life Insurance Co. (Seattle) an Max Horkheimer, 16.01.1950;

Solar radiation over and under sea ice and photographic quantification of Ice algal aggregates during the POLARSTERN cruise ARK-XXVII/3 (IceArc) in summer 2012

The ice cover of the Arctic Ocean has been changing dramatically in the last decades and the consequences for the sea-ice associated ecosystem remain difficult to assess. Algal aggregates underneath sea ice have been described sporadically but the frequency and distribution of their occurrence is not well quantified. We used upward looking images obtained by a remotely operated vehicle (ROV) to derive estimates of ice algal aggregate biomass and to investigate their spatial distribution. During the IceArc expedition (ARK-XXVII/3) of RV Polarstern in late summer 2012, different types of algal aggregates were observed floating underneath various ice types in the Central Arctic basins. Our results show that the floe scale distribution of algal aggregates in late summer is very patchy and determined by the topography of the ice underside, with aggregates collecting in dome shaped structures and at the edges of pressure ridges. The buoyancy of the aggregates was also evident from analysis of the aggregate size distribution. Different approaches used to estimate aggregate biomass yield a wide range of results. This highlights that special care must be taken when upscaling observations and comparing results from surveys conducted using different methods or on different spatial scales.

Solar irradiance over and under seasonal land-fast sea ice off Barrow, Alaska, in 2010

The amount of solar radiation transmitted through Arctic sea ice is determined by the thickness and physical properties of snow and sea ice. Light transmittance is highly variable in space and time since thickness and physical properties of snow and sea ice are highly heterogeneous on variable time and length scales. We present field measurements of under-ice irradiance along transects under undeformed land-fast sea ice at Barrow, Alaska (March, May, and June 2010). The measurements were performed with a spectral radiometer mounted on a floating under-ice sled. The objective was to quantify the spatial variability of light transmittance through snow and sea ice, and to compare this variability along its seasonal evolution. Along with optical measurements, snow depth, sea ice thickness, and freeboard were recorded, and ice cores were analyzed for chlorophyll a and particulate matter. Our results show that snow cover variability prior to onset of snow melt causes as much relative spatial variability of light transmittance as the contrast of ponded and white ice during summer. Both before and after melt onset, measured transmittances fell in a range from one third to three times the mean value. In addition, we found a twentyfold increase of light transmittance as a result of partial snowmelt, showing the seasonal evolution of transmittance through sea ice far exceeds the spatial variability. However, prior melt onset, light transmittance was time invariant and differences in under-ice irradiance were directly related to the spatial variability of the snow cover.

(Table 1) Composition of DSDP Hole 37-334 clinopyroxenes

Recent studies of abyssal peridotites (Johnson et al., 1990, doi:10.1029/JB095iB03p02661), mid-ocean-ridge basalts (MORBs) (McKenzie, 1985, doi:10.1016/0012-821X(85)90001-9) and their entrained melt inclusions (Sobolev and Shimizu, 1993, doi:10.1038/363151a0; Humler and Whitechurch, 1988, doi:10.1016/0012-821X(88)90055-6) have shown that fractional melting of the upwelling sub-oceanic mantle produces magmas with a much wider range of compositions than erupted MORBs. In particular, it seems that strongly depleted primary magmas are routinely produced by melting beneath ridges (Johnson et al., 1990, doi:10.1029/JB095iB03p02661). The absence of strongly depleted melts as erupted lavas prompts the question of how long such magmas survive beneath ridges, before their distinctive compositions are concealed by mixing with more enriched magmas. Here we report mineral compositions from a unique suite of oceanic cumulates recovered from DSDP Site 334 (Aumento et al., doi:10.2973/dsdp.proc.37.1977), which indicate that the rocks crystallized from basaltic liquids that were strongly depleted in Na, Ti, Zr, Y, Sr and rare-earth elements relative to any erupted MORB. It thus appears that the magmatic plumbing system beneath the Mid-Atlantic Ridge permitted strongly depleted magmas to accumulate in a magma chamber and remain sufficiently isolated to produce cumulate rocks. Even so, spatial heterogeneity in the compositions of high-calcium pyroxenes suggests that in the later stages of solidification these rocks reacted with infiltrating enriched basaltic liquids.