Marilén Fernández

Climatic and Environmental History of Isla de los Estados, Argentina

This book is the result of 10 years of scientific research carried out by the authors on Isla de los Estados. The research includes their doctoral theses and many published scientific papers related to the island. Isla de los Estados (Staten Island) is located at the southernmost end of South America, forming part of the Argentine province of Tierra del Fuego, Antarctica and South Atlantic Islands. It is included within the Argentine continental shelf by which it is connected to the Islas Malvinas/Falklands and the Isla Grande de Tierra del Fuego. It is separated from the latter by the Le Maire Strait, which is only 30 km wide. It is located at a distance of ca. 30 km southeast from Peninsula Mitre, Isla Grande de Tierra del Fuego (Main Island of Tierra del Fuego) and has a surface area of 496 km2. The island, due to its geographical location, conforms a unique and sensitive area for Quaternary paleoecological and paleoclimatic studies, providing information on the atmospheric and environmental conditions from cold-temperate high latitudes in the Southern Hemisphere. This book can be divided into two principal parts. The first part (chapters 1 to 4) contains different social and natural aspects of this remote island and includes chapters on the scientific and historical background, physiography with topographical and hydrographical descriptions, climate and oceanographic circulation, vegetation and geology (including stratigraphy, structural geology, and geological history). The second part (chapters 5 to 10) comprises a reconstruction of the paleoenvironmental, paleoclimatic, and paleogeographic history of the island from the Last Glacial Maximum to present, correlating with other paleoecological records from the southern part of Isla Grande de Tierra del Fuego and Patagonia. This second part also includes a geomorphological chapter (Chapter 5) with a characterization of the principal erosive glacial landforms in Isla de los Estados constructed by means of morphometric analysis, inventories, maps, paleogeographic, and glacial models. Based on a geomorphological analysis, a timeless glacial model of the island is presented, that is, a model that could be applied to any of the Pleistocene glaciations of the region. In Chapter 6, they reconstruct the paleogeographic evolution of the Isla de los Estados for the period spanning the Last Glacial Maximum (LGM, ca. 24 cal. ka B.P.) to present using the global sea-level rise curve proposed by Fleming et al. for this period and the Global Mapper 10 program. A vegetation reconstruction (Chapter 7) was made in western Isla de los Estados using palynological analysis for the last 13,000 cal year BP. In Chapter 8 they present the diatom analysis results from glaciolacustrine and lacustrine sedimentary sequences. And in Chapter 9 they evaluated the paleoenvironment and paleoclimatic conditions that prevailed during the Late Pleistocene-Holocene times based on pollen and diatom analysis from three 14C-dated peat bogs and lakes. Finally (Chapter 10), the book concludes with a review of the island’s archaeology and the relationship between the paleoenvironmental history and human occupation of this island.This chapter explores the paleoenvironmental situation of Isla de los Estados and its relationship with the archaeological record left behind by ancient canoeing people. One of the aims of this chapter was to analyze why there is no evidence of human occupation at Isla de los Estados during the Middle Holocene, and to discuss if this could be related to certain paleoenvironmental conditions prevailing in this area and the adjacent seas. The low number of tools or artifacts found in these sites is linked with feeding activities such as the catch of fish and terrestrial animals. Currently, and continuously since 1977, a contingent of the Argentine Navy has been stationed in Puerto Parry. This post is occupied by four people. Isla de los Estados is without doubt one of the most isolated and uninhabited places in the Argentine territory. All information provided in this book is well documented and clearly expressed. It is easy and enjoyable to read. Photographs and graphics are of excellent quality and representative of the data provided.

Compensation of environmental parameters for driving-aid ultrasonic systems in foggy conditions

The use of driving-aid ultrasonic systems in low visibility conditions due to fog, makes it necessary to study the influence of environmental parameters such as temperature, humidity or air velocity on the ultrasonic propagation. The present work tries to construct simple empirical models for velocity and echo amplitude that includes temperature and relative humidity as inputs. We present the results obtained in the modelling of the ultrasonic propagation in environments with variable conditions of humidity and temperature, including foggy conditions

Reconstruction of Paleoenvironmental Conditions During Late Glacial and Holocene Times in Isla de los Estados and Their Correlation with the Beagle Channel and Southern Patagonia

Late Glacial-Holocene environmental conditions were interpreted in Isla de los Estados from palynological and diatomological analysis and linked also with geoquimical studies. The deglaciation started after 16,000 cal. years B.P. followed by a rapid glacial retreat under gradually warmer conditions, with alternation of drier and wetter periods until ca. 12,800 cal. years B.P. Between ca. 12,600 and 10,300 cal. years B.P. the plant communities indicated moderately cold to mild and arid climatic conditions. During the Early Holocene the expansion of Nothofagus forests is interpreted as a signal of increasing temperature and precipitation in spite of the humidity levels being then lower than today. Around 8,000–6,000 cal. years B.P. the marine diatom assemblages and geoquimical analysis indicates the Middle Holocene marine transgression. An abrupt rise of arboreal taxa occurred between ca. 8,300 and 5,500 cal. yr BP related to increased effective precipitation that culminated with the establishment and persistence of closed-canopy forest communities of Sub-Antarctic Evergreen Forest. The diatoms assemblages suggest wetter conditions, and a greater development of aquatic vegetation from ca. 4,800 cal. years B.P. From ca. 2,700 cal. years B.P. an important vegetation change in the area can be seen, probably as a consequence of warmer and drier conditions.

History, Previous Works and Physiography

Isla de los Estados (Staaten Island) is located at the southernmost end of South America, forming part of the argentina province of Tierra del Fuego, Antarctica and South Atlantic Islands. The island, due to its geographical location, conforms a unique and sensitive area for Quaternary palaeoecological and palaeoclimatic studies giving information on the atmospheric and environmental conditions from cold-temperate high latitudes in the Southern Hemisphere. It is located at a distance of ca. 30 km southeast from Peninsula Mitre, Isla Grande de Tierra del Fuego (Main Island of Tierra del Fuego) and has a surface area of 496 km2. It is the southeastern end of the Andes range above present sea level. The topography is characteristic of terrain repeatedly glaciated during the Quaternary. At the eastern area of the island the topography is less rugged than at its central and western areas.Isla de los Estados was discovered in the year 1616. Currently, and continuously since 1977, a contingent of the Argentine Navy has been stationed in Puerto Parry. These people represent the entire population of the island together with the post on Observatorio Island (Ano Nuevo Island).