Historical Patterns and Effects of Changes In Adirondack Climates Since the Early 20th Century

Analysis of weather data from seven United States Historical Climatology Network stations in the Adirondack region reveals statistically significant warming over the last 30 years during June and September, but no significant trends in the other months. The warmest intervals of the 1926-2005 period were the early 1930s, 1949-1954, and 1997-2003. These findings are consistent with similar analyses of northern New York weather data by Kathie Delio, but somewhat less so with earlier works by the first author and others. In this paper, we also discuss the effects of various interpretive methodologies on the study of regional climate and present new phonological data from the Adirondack region. We find little evidence of major biotic responses to weather trends in recent decades, perhaps because most such trends are still largely obscured by inter-annual variability, but a significant reduction in the duration of ice cover has occurred on local lakes. In addition, an increase of river discharge during the 20th century probably reflects a long-term increase in precipitation, particularly during fall

Contaminant Concentrations in Adirondack Soil and Sediment

Paired soil and sediment samples were collected along a transect across northern New York from Lake Ontario to the Tug Hill Plateau to Indian Lake in the Central Adirondack Mountains. The samples were analyzed for four classes of compounds including polychlorinated biphenyl.s, polyaro­matic hydrocarbons, select chlorinated pesticides, and inorganic elements and metals with different origins, usage history, and chemical properties. In general, the concentrations of these contaminants were higher in soil than sediment but relatively low compared to other more developed areas, consistent with the remoteness of the Adirondack region and limited permanent population. Trends in the data suggest that the concentrations of contaminants, particularly high molecular weight organic compounds, are generally greater closer to Lake Ontario. The reason(s) for this remain unclear, but are likely related to the large amounts of lake-effect precipitation the Tug Hill area receives and scavenging of contaminants by rain and snow. Levels reported for contaminants investigated in this study are generally lower than those reported elsewhere in the United States, and likely reflect the low population density of the region and less intensive !and use

Enriched Grenvillian lithospheric mantle as a consequence of long-lived subduction beneath Laurentia

Geochemical and Nd isotopic data from mafic and newly discovered ultramafic rocks in the Adirondack Lowlands suggest widespread enrichment of the lithospheric mantle under the Grenville Province. Incompatible element abundances and previously published Hf TDM (zircon) (depleted mantle model age) and Nd TDM ages from rocks of the anorthosite-mangerite-charnockite-granite suite in the Adirondack Highlands document similar enrichment in the lower crust and its strong influence on subsequent magmatic events throughout the Ontario-Quebec-Adirondack segment of the Grenville Province. Likely the consequence of long-lived (ca. 1.4–1.2 Ga) northwest-directed subduction along the southeast edge of Laurentia (previously proposed Andean margin), this enrichment is similar to that associated with the vast (>240,000 km2) ultrapotassic province of the western Churchill Province. Enrichment of the lithospheric mantle beneath orogenic belts is a predictable and important differentiation process that has operated on Earth for at least the past 3 b.y