Correspondence Analysis for Mineral Commodity Research: An Example Workflow for Mineralized Calderas, Southwest United States

Bostrichoclerus bicornus Van Dyke is known from southwest United States and northwest Mexico. To date, only two specimens have been captured: the holotype, collected on Isla Angel de la Guarda, in the Gulf of California, Mexico, and a second individual collected in San Bernardino County, California, United States. The original description of B. bicornus is brief and lacks any images. Considering its rarity, we present the redescription of this species based on the examination of the holotype and compare this taxon to similar genera of New World Tillinae. Images of the holotype and the Bostrichoclerus specimen collected in southern California are given. We conclude that B. bicornus is undoubtedly a member of the subfamily Tillinae with unclear intergeneric relations in the group.

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Interdecadal Seesaw of Precipitation Variability between North China and the Southwest United States

Journal of Climate ◽

10.1175/jcli-d-18-0082.1 ◽

2019 ◽

Vol 32 (10) ◽

pp. 2951-2968 ◽

Cited By ~ 4

Author(s):

Qing Yang ◽

Zhuguo Ma ◽

Peili Wu ◽

Nicholas P. Klingaman ◽

Lixia Zhang

Keyword(s):

United States ◽

North Pacific ◽

Large Scale ◽

North China ◽

Atlantic Multidecadal Oscillation ◽

Precipitation Variability ◽

Circulation Anomaly ◽

Potential Predictability ◽

Southwest United States ◽

Rainfall Anomalies

Abstract This paper reports a consistent seesaw relationship between interdecadal precipitation variability over North China and the Southwest United States, which can be found in observations and simulations with several models. Idealized model simulations suggest the seesaw could be mainly driven by the interdecadal Pacific oscillation (IPO), through a large-scale circulation anomaly occupying the entire northern North Pacific, while the Atlantic multidecadal oscillation (AMO) contributes oppositely and less. Modulation of precipitation by the IPO tends to be intensified when the AMO is in the opposite phase, but weakened when the AMO is in the same phase. The warm IPO phase is associated with an anomalous cyclone over the northern North Pacific; consequently, anomalous southwesterly winds bring more moisture and rainfall to the Southwest United States, while northwesterly wind anomalies prevail over North China with negative rainfall anomalies. The east–west seesaw of rainfall anomalies reverses sign when the circulation anomaly becomes anticyclonic during the cold IPO phase. The IPO-related tropical SST anomalies affect the meridional temperature gradient over the North Pacific and adjacent regions and the mean meridional circulation. In the northern North Pacific, the atmospheric response to IPO forcing imposes an equivalent barotropic structure throughout the troposphere. An important implication from this study is the potential predictability of drought-related water stresses over these arid and semiarid regions, with the progress of our understanding and prediction of the IPO and AMO.

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