Pollen and grain size records in abyssal sediments of the northwest Pacific Ocean as proxies of Plio-Pleistocene climate change /

A distinctive period of global change occurred during the PUocene between the warm Miocene and subsequent Quaternary cooling. Samples from Ocean Drilling Project Site 11 79 (-5586 mbsl, 41°4'N, 159°57'E), Site 881 (-5765 mbsl, 47°6.133'N, 161°29.490'E) and Site 882 (-3255 mbsl, 50°22'N, 167°36'E) were studied to determine the magnitude and composition ofterrigenous flux to the western mid-latitude North Pacific and its relation to climate change in East Asia since the mid-Pliocene. Dust-sized particles (including pollen), sourced from the arid regions and loess plateaus in East Asia are entrained by prevailing westerly winds and transported to the midlatitude northwest North Pacific Ocean. This is recorded by peaks in the total concentration of pollen and spores, as well as the mean grain size of allochthonous and autochthonous silicate material in abyssal marine sediments. Aridification of the Asian interior due to the phased uplift of the Himalayan-Tibetan Plateau created the modem East Asian Monsoon system dominated by a strengthening of the winter monsoon. The winter monsoon is further enhanced during glacials due to the expansion of desert and steppe environments at the expense ofwoodlands and forests recorded by the composition of palynological assemblages. The late Pliocene-Pleistocene glacials at ODP Sites 1 179, 881, and 882 are characterized by increases in grain size, magnetic susceptibility, pollen and spore concentrations around 3.5-3.3, 2.6-2.4, 1.7-1.6, and 0.9-0.7 Ma (ages based on magnetostratigraphic and biostratigraphic datums). The peaks during these times are relatively rich in pollen taxa derived primarily from steppe and boreal vegetation zones, recording cool, dry climates. The overall size increase of sediment and abundance of terrestrial palynomorphs record enhanced wind strength. The increase in magnitude of pollen and spore concentrations as well as grain size record global cooling and Northern Hemisphere glaciation. The peaks in grain size as well as pollen and spore abundance in marine sediments correlate with the mean grain size of loess in East Asia, consistent with the deflation of unarmoured surfaces during glacials. The transport of limiting nutrients to marine environments enhanced sea surface productivity and increased the rate of sediment accumulation.

Letter - Andrew Cowan to William Cowan

A letter from Andrew Cowan to his son William Cowan 29 Septemer 1841. The letter reads "Dear William, I have taken my pen the third time since I have received any word from you, my first letter was about the beginning of the year, and the second in the month of April with John Armstrong of Northhouse, he sailed from Liverpool the fifteen of that month with his sisters Jane and Jenny and their two children. I received a letter from him dated Cleavland in the State of Ohio the 6 of June. He did not intend stopping in that place. The leaves us all well for any thing that I know, but I have not heard from Andrew since March altho I have writen to him three months since your Mother and I are both sore faild altho we have tolerable good health for which we desire to be thankfull to the giver of all our mercies, which are new every day, that we may be found in Christs and clothed in his imputed righteousness at the last, for in him is only found true happyness. We have had another cold wet Summer and the crops is far back ------ not light, the price of -----is high and trade bad, but sheep and cattle are high. Cattle have not been higher since the French war, but the cattle trade is very bad at present and the opperatives out of imployment and consequently verrry badly of. If none of my former letters have reached you this will inform you that James is at Lanshawburn, and gets imployment all the year, he keeps a cow and five or six sheep, they have three children, Mary, Hannah, and Andrew; I was there after clipping time seeing them, they seem to be verry happy. James Lamb is well he was here the other night, he has got two letters from his son Adam this Summer; they are still in the same place and will finish their job this fall, and seem to be doing well, your Uncle Adam Scott and family are well. John was there lately there is little prospect of his getting to America as the money that was left him is not got yet and will not for some time, If ever this reach you, you must let us know how all the Scotch people that are near you, that went from this place of the Country are doing, as their freinds are anxious to hear from them, perticularly if you know what is becomed of Alexander Hoggs widow and family of ------hill, as I was desired to write to you about them - I got a letter from John Miller dated Gatt but I understand it is a long way from your place he was a gentleman and had the charge of a farm and seems verry ----- Now William if this ever reach you, you must excuse me for not filling this letter up, but if I receive an answer I promise to fill the next better, We all join in our love and respect to you and family. From your loving Father Andrew Cowan