Alexander Agassiz, 1835-1910

Biography with photograph

Letter and Recollections of Alexander Agassiz: The 1891 Albatross Expedition

Presented here is another in the list of historic accounts of iconic research cruises of the USFC Steamer Albatross, this a reminiscence of the renowned scientist Alexander Agassiz edited by his son G. R. Agassiz, a chapter from the volume “Letters and Recollections of Alexander Agassiz,” published in 1913. Agassiz made three major cruises in the Albatross in 1891, 1899–1900, and 1904–05, adding greatly to the world’s store of specimens and knowledge of thalasography, his favored term for oceangraphy, and specifically of the Pacific Ocean. Having made important cruises and studies with the Blake in the Caribbean, he sought to do comparable research in the Pacific. His opportunity came in 1890, and with the consent of President Benjamin Harrison, he took charge of this Albatross research cruise, paying much of the expense himself. In contrast with the other ships he had been on, he found the laboratories, equipment, and furnishings to be comparatively luxurious and extremely well appointed for his work. Further, the Albatross was then captained by Lieutenant Commander Zera Luther Tanner who seemed to take as much interest in the oceanographic research as did the scientists, and Agassiz appreciated working with him, too. Little of the original text has been altered, and readers are cautioned that some of the views expressed may reflect unfortunate prejudices of that era toward individuals, nationalities, etc.

A mechanism for the link between solar-irradiance variations and regional precipitation

Although the mechanisms of climatic fluctuations are not completely understood, changes in global solar irradiance show a link with regional precipitation. A proposed mechanism for this linkage begins with absorption of varying amounts of solar energy by tropical oceans, which may aid in development of ocean temperature anomalies. These anomalies are then transported by major ocean currents to locations where the stored energy is released into the atmosphere, altering pressure and moisture patterns that can ultimately affect regional precipitation. Correlation coefficients between annual averages of monthly differences in empirically modeled solar-irradiance variations and annual state-divisional precipitation values in the United States for 1950 to 1988 were computed with lag times of 0 to 7 years. The highest correlations (R=0.65) occur in the Pacific Northwest with a lag time of 4 years, which is about equal to the travel time of water within the Pacific Gyre from the western tropical Pacific Ocean to the Gulf of Alaska. With positive correlations, droughts coincide with periods of negative irradiance differences (dry, high-pressure development), and wet periods coincide with periods of positive differences (moist, low-pressure development).

Sea surface temperature and the subsequent freshwater survival rate of some salmon stocks: a surprising link between the climate of land and sea

Previous consideration of the relationship between climate and the survival rate of Pacific salmon eggs and fry has been confined to effects of large variation in the ambient freshwater environment; e.g., stream discharge, temperature, turbidity. This analysis shows sea surface temperatures during the last year of life of maturing adult salmon are also strongly associated with the subsequent survival rate of salmon eggs and fry is fresh water, presumably through development of the future eggs or sperm. In several stocks of three species of North American salmon, the association between the "marine" climate and egg survival is stronger than, or additive to, any estimated climatic association in fresh water. This apparent and surprising link between fresh water and the distant ocean has some interesting and complex implications for management of future salmon production.