Fish and habitat community assessments on North Carolina shipwrecks: potential sites for detecting climate change in the graveyard of the Atlantic

The Monitor National Marine Sanctuary (MNMS) was the nation’s first sanctuary, originally established in 1975 to protect the famous civil war ironclad shipwreck, the USS Monitor. Since 2008, sanctuary sponsored archeological research has branched out to include historically significant U-boats and World War II shipwrecks within the larger Graveyard of the Atlantic off the coast of North Carolina. These shipwrecks are not only important for their cultural value, but also as habitat for a wide diversity of fishes, invertebrates and algal species. Additionally, due to their unique location within an important area for biological productivity, the sanctuary and other culturally valuable shipwrecks within the Graveyard of the Atlantic are potential sites for examining community change. For this reason, from June 8-30, 2010, biological and ecological investigations were conducted at four World War II shipwrecks (Keshena, City of Atlanta, Dixie Arrow, EM Clark), as part of the MNMS 2010 Battle of the Atlantic (BOTA) research project. At each shipwreck site, fish community surveys were conducted and benthic photo-quadrats were collected to characterize the mobile conspicuous fish, smaller prey fish, and sessile invertebrate and algal communities. In addition, temperature sensors were placed at all four shipwrecks previously mentioned, as well as an additional shipwreck, the Manuela. The data, which establishes a baseline condition to use in future assessments, suggest strong differences in both the fish and benthic communities among the surveyed shipwrecks based on the oceanographic zone (depth). In order to establish these shipwrecks as sites for detecting community change it is suggested that a subset of locations across the shelf be selected and repeatedly sampled over time. In order to reduce variability within sites for both the benthic and fish communities, a significant number of surveys should be conducted at each location. This sampling strategy will account for the natural differences in community structure that exist across the shelf due to the oceanographic regime, and allow robust statistical analyses of community differences over time.

Fish for the future: Fisheries development and food security for Kiribati in an era of global climate change

The Republic of Kiribati is a vast South Pacific island group with one of the largest exclusive economic zones (EEZs) in the world. Kiribati waters support a wealth of marine fisheries activities. These activities occur in oceanic, coastal and inshore environments and range from large, foreign, industrial-scale oceanic fishing operations to small-scale, domestic, inshore subsistence fisheries, aquaculture and recreational fisheries. Kiribati has developed a framework of domestic and international governance arrangements that are designed to sustainably manage its wealth of marine resources. The report provides background information for fisheries projects in Kiribati that aim to build food security, improve artisanal livelihoods and strengthen community engagement in fisheries governance. It provides information on the current status of Kiribati fishery resources (oceanic and coastal), their current governance and future challenges. Fish and fisher alike pay little heed to maritime boundaries and bureaucratic distinctions. This report covers both sides of the oceanic/coastal boundary because of the I-Kiribati communities’ interest in oceanic fisheries such as tuna and their heavy dependence on its fisheries resources for food security and economic development. The report focuses on two potential pilot sites for community-based fisheries management projects: North Tarawa and Butaritari.

Determining the role of linear and nonlinear interactions in records of climate change: possible solar influences in annual to century-scale records

Time series analysis methods have traditionally helped in identifying the role of various forcing mechanisms in influencing climate change. A challenge to understanding decadal and century-scale climate change has been that the linkages between climate changes and potential forcing mechanisms such as solar variability are often uncertain. However, most studies have focused on the role of climate forcing and climate response within a strictly linear framework. Nonlinear time series analysis procedures provide the opportunity to analyze the role of climate forcing and climate responses between different time scales of climate change. An example is provided by the possible nonlinear response of paleo-ENSO-scale climate changes as identified from coral records to forcing by the solar cycle at longer time scales.

The terrestrial paleorecord of climate change over the past thousand years in the Canadian Rockies [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): High alpine environments provide a variety of paleorecords based on physical (glaciers, glacio-lacustrine sedimentation) and biological systems (tree rings, tree-line fluctuations). These records have varying temporal resolution and contain different climate-related signals but, in concert, provide a more comprehensive reconstruction of past climates than is possible from any single archive.

High-resolution record of climate change in the Owens Lake Basin, California, for the period 52,500 to 12,500 YBP

EXTRACT (SEE PDF FOR FULL ABSTRACT): High-resolution oxygen-18 and total inorganic carbon (TIC) studies of cored sediments from the Owens Lake Basin, California, indicate that Owens Lake was hydrologically open (overflowing) most of the time between 52,500 and 12,500 carbon-14 YBP. ... The lack of a strong correspondence between North Atlantic climate records and the Owens Lake delta-oxygen-18 record has two possible explanations: (1) the sequence of large and abrupt climate change indicated in North Atlantic records is not global in scope and is largely confined to the North Atlantic and surrounding areas, or (2) Owens Lake is located in a part of the Great Basin that is relatively insensitive to the effects of climate perturbations recorded in the North Atlantic region.

A late-Holocene pollen record from Lower Pahrangat Lake, southern Nevada, USA: high resolution paleoclimatic records and analysis of environmental responses to climate change

EXTRACT (SEE PDF FOR FULL ABSTRACT): High resolution paleobotanical records provide sufficient detail to correlate events regionally. Once correlated events can be examined in tandem to determine the underlying inputs that fashioned them. Several localities in the Great Basin have paleobotanical records of sufficient detail to generate regional reconstructions of vegetation changes for the last 2 ka and provide conclusions as to the climates that caused them.