Valley-fill alluviation during the Little Ice Age (ca. A.D. 1400–1880), Paria River basin and southern Colorado Plateau, United States

2002 ◽  
Vol 114 (12) ◽  
pp. 1550-1563 ◽  
Author(s):  
Richard Hereford
Author(s):  
Т.Р. Макарова

Изучение разреза торфяника в бассейне р. Большая Уссурка (Приморье) позволило выявить изменения увлажненности. Установлен период продолжительных засух, совпадавших с ослаблением летнего муссона. Несмотря на сухие условия проходили паводки, вызванные тайфунами или глубокими циклонами. Влажными были малый оптимум голоцена и малый ледниковый период, характеризовавшиеся усилением циклогенеза. Отмечены кратковременные флуктуации увлажнения, периоды с разной паводковой активностью. Study of the peat bog section in the river basin Bolshaya Ussurka (Primorye) made it possible to distinguish periods with different moisture. Period of prolonged droughts was established, coinciding with the weakening of the summer monsoon. Dry conditions did not exclude floods due to the passage of typhoons or deep cyclones. The low optimum of the Holocene and the Little Ice Age, characterized by increased cyclogenesis, were humid. Short-term fluctuations of moisture, periods with different flood activity were noted.


1986 ◽  
Vol 8 ◽  
pp. 65-68 ◽  
Author(s):  
Jane G. Ferrigno

Grasshopper Glacier is a cirque glacier in the central Rocky Mountains of the United States. It is a remnant of the “Little Ice Age”, rather than the more widespread and older Pinedale Glaciation. The glacier has not been monitored on a regular basis and very few maps have been published of the area, but it has been studied, photographed, occasionally mapped, and described by scientific and non-scientific groups, at different times since 1898. These photographic, cartographic, and written records make it possible to trace the fluctuations of this glacier since 1898. Grasshopper Glacier has had periods of positive mass balance, but the overall trend has been negative, with accelerated melting in recent years. It is estimated that Grasshopper Glacier has lost about 50% of its area and as much as 90% of its volume, since 1898. Other Rocky Mountain glaciers are experiencing similar wastage and, if current conditions continue, these glaciers will disappear by the middle of the next century.


2007 ◽  
Vol 41 (3) ◽  
pp. 397-401 ◽  
Author(s):  
Gregory A. Zielinski ◽  
P. Thompson Davis

ABSTRACT The type Temple Lake moraine lies about 3 km beyond and roughly 120 m lower than the modern glacier margin and the Gannett Peak (Little Ice Age) moraines deposited in the last few centuries. Because numerous glacial deposits throughout the western United States have been correlated to the Temple Lake moraine its age is important. We retrieved two sediment cores up to six meters long from Rapid Lake, outside the outer type Temple Lake moraine. The 383-413 cm depth dates 11,770 ± 710 yrs (GX-11,772), which we believe reflects the time when silt flux into Rapid Lake was abruptly reduced by the formation of a new sediment trap at Miller Lake as the valley glacier receded from its position at the outer Temple Lake moraine. A radiocarbon date of 11,400 ± 630 yrs BP (GX-12,719) obtained from the lower basin of Temple Lake, inside the inner type Temple Lake moraine, supports this interpretation. Sediments from Miller Lake, inside the outer Temple Lake moraine, that date 8300 ± 475 yrs BP (GX-12,277) are probably well above the bottom of the lake sediment sequence and possibly thousands of years younger than the moraine. We feel that the type Temple Lake moraine dates about 12,000 yrs BP, thus is Late Pleistocene in age. This interpretation is supported by maximum percentages of organic detritus in lake sediments between 10,000 and 8,000 yrs BP, and challenges BEGET's (1983) suggestion that the type Temple Lake moraine is early Holocene in age, a period he calls "Mesogiaciation".


1986 ◽  
Vol 8 ◽  
pp. 65-68 ◽  
Author(s):  
Jane G. Ferrigno

Grasshopper Glacier is a cirque glacier in the central Rocky Mountains of the United States. It is a remnant of the “Little Ice Age”, rather than the more widespread and older Pinedale Glaciation. The glacier has not been monitored on a regular basis and very few maps have been published of the area, but it has been studied, photographed, occasionally mapped, and described by scientific and non-scientific groups, at different times since 1898. These photographic, cartographic, and written records make it possible to trace the fluctuations of this glacier since 1898. Grasshopper Glacier has had periods of positive mass balance, but the overall trend has been negative, with accelerated melting in recent years. It is estimated that Grasshopper Glacier has lost about 50% of its area and as much as 90% of its volume, since 1898. Other Rocky Mountain glaciers are experiencing similar wastage and, if current conditions continue, these glaciers will disappear by the middle of the next century.


1976 ◽  
Vol 41 (2) ◽  
pp. 206-208 ◽  
Author(s):  
W. Raymond Wood

AbstractData from United States General Land Office Surveys are commonly used to create vegetation models for the American Pioneer period. These models are then used as baselines for understanding past biotic change. It should be realized that many of these surveys were made near the end of a climatic episode (the Neo-Boreal or "Little Ice Age") when world temperatures were much lower than at the present time. These baselines therefore do not represent vegetational responses to a climatic regime like that of the present, and the vegetation models must be interpreted accordingly.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
David P. Pompeani ◽  
Broxton W. Bird ◽  
Jeremy J. Wilson ◽  
William P. Gilhooly ◽  
Aubrey L. Hillman ◽  
...  

AbstractDrought has long been suspected as playing an important role in the abandonment of pre-Columbian Native American settlements across the midcontinental United States between 1350 and 1450 CE. However, high-resolution paleoclimatic reconstructions reflecting local effective moisture (the ratio of precipitation to evaporation) that are located in proximity to Mississippi period (1050–1450 CE) population centers are lacking. Here, we present a 1600-year-long decadally resolved oxygen isotope (δ18O) record from Horseshoe Lake (Collinsville, IL), an evaporatively influenced oxbow lake that is centrally located within the largest and mostly densely populated series of Mississippian settlements known as Greater Cahokia. A shift to higher δ18O in the Horseshoe Lake sediment record from 1200 to 1400 CE indicates that strongly evaporative conditions (i.e., low effective moisture) were persistent during the leadup to Cahokia’s abandonment. These results support the hypothesis that climate, and drought specifically, strongly impacted agriculturally based pre-Columbian Native American cultures in the midcontinental US and highlights the susceptibility of this region, presently a global food production center, to hydroclimate extremes.


Author(s):  
W.P. De Lange

The Greenhouse Effect acts to slow the escape of infrared radiation to space, and hence warms the atmosphere. The oceans derive almost all of their thermal energy from the sun, and none from infrared radiation in the atmosphere. The thermal energy stored by the oceans is transported globally and released after a range of different time periods. The release of thermal energy from the oceans modifies the behaviour of atmospheric circulation, and hence varies climate. Based on ocean behaviour, New Zealand can expect weather patterns similar to those from 1890-1922 and another Little Ice Age may develop this century.


2013 ◽  
Vol 6 (1) ◽  
pp. 29-36 ◽  
Author(s):  
Anastasia Gornostayeva ◽  
◽  
Dmitry Demezhko ◽  
◽  
Keyword(s):  

2020 ◽  
Vol 42 (1) ◽  
pp. 4-12
Author(s):  
Valeriy Fedorov ◽  
Denis Frolov

Sign in / Sign up

Export Citation Format

Share Document