Icehouse Earth

On Gaia ◽  
2013 ◽  
Author(s):  
Toby Tyrrell
Keyword(s):  
Sea Level ◽  
Total Mass ◽  
Ice Ages ◽  
Dry Land ◽  
The Past ◽  
Long Duration ◽  
Shelf Seas ◽  
James Lovelock ◽  
Favorable State ◽  
Life On Earth

This chapter compares the life that evolution produced during the past cold and warm climates of long duration. The dominant climatic state of the last several million years has been ice ages. James Lovelock has argued that these are a more favorable state for life on Earth than the present interglacials. This does not, however, sit well with various observations. During ice ages: (i) there was less land free of ice; (ii) much of the most productive parts of the ocean, the shelf seas, were turned into dry land by lower sea level; and (iii) the total mass of carbon locked up in vegetation and soils was only about half as much as today. Not only were ice ages unfortunate episodes for life on Earth, but also, conversely, the Earth during the Cretaceous was possibly even more congenial than it is today, although the evidence is not conclusive on this point.

Interglacial Climates and Antarctic Ice Surges

1972 ◽  
Vol 2 (3) ◽  
pp. 401-408 ◽  
Author(s):  
John T. Hollin
Keyword(s):  
Gulf Of Mexico ◽  
Sea Level ◽  
Ice Core ◽  
Ice Sheet ◽  
Washington Dc ◽  
Ice Ages ◽  
Last Interglacial ◽  
Antarctic Ice Sheet ◽  
The Past ◽  
Pollen Diagrams

Wilson's theory of ice ages implies that the present interglacial will end with, or at least be interrupted by, an Antarctic ice sheet “surge”. Such surges in the past would have caused distinctive rises of sea level: by 10–30 m, in 100 yr or much less, and precisely at the break of climate at the end of each interglacial. Lithostratigraphic, pollen-analytic and radiometric evidence hinting at such a rise (to 17 m?) late in the last interglacial (at about 95,000 BP?) is found in the Spencer's Point formation in Bermuda, the Ladson and Canepatch formations in S. Carolina, the Norfolk formation in Virginia, and above the Walker interglacial swamp in Washington, DC. The strongest evidence that could be found against this rise would be pollen diagrams up toward 17 m which showed continuously freshwater conditions late in the interglacial. Features that might be explained by a surge occur in the Camp Century ice core, in Atlantic, Caribbean and Gulf of Mexico marine cores, and in the Orgnac stalagmite.

scholarly journals Criminology: Some lines of flight

2021 ◽  
Vol 54 (1) ◽  
pp. 21-33
Author(s):  
Julie Berg ◽  
Clifford Shearing
Keyword(s):  
21St Century ◽  
Energy Systems ◽  
Social Practices ◽  
Smart Phones ◽  
40Th Anniversary ◽  
The Past ◽  
Domain Of Existence ◽  
James Lovelock ◽  
The 1960S ◽  
Space Of Flows

The 40th Anniversary Edition of Taylor, Walton and Young’s New Criminology, published in 2013, opened with these words: ‘The New Criminology was written at a particular time and place, it was a product of 1968 and its aftermath; a world turned upside down’. We are at a similar moment today. Several developments have been, and are turning, our 21st century world upside down. Among the most profound has been the emergence of a new earth, that the ‘Anthropocene’ references, and ‘cyberspace’, a term first used in the 1960s, which James Lovelock has recently termed a ‘Novacene’, a world that includes both human and artificial intelligences. We live today on an earth that is proving to be very different to the Holocene earth, our home for the past 12,000 years. To appreciate the Novacene one need only think of our ‘smart’ phones. This world constitutes a novel domain of existence that Castells has conceived of as a terrain of ‘material arrangements that allow for simultaneity of social practices without territorial contiguity’ – a world of sprawling material infrastructures, that has enabled a ‘space of flows’, through which massive amounts of information travel. Like the Anthropocene, the Novacene has brought with it novel ‘harmscapes’, for example, attacks on energy systems. In this paper, we consider how criminology has responded to these harmscapes brought on by these new worlds. We identify ‘lines of flight’ that are emerging, as these challenges are being met by criminological thinkers who are developing the conceptual trajectories that are shaping 21st century criminologies.

Salt marshes adjustment to anthropogenic pressures and sea-level rise

2021 ◽  
Author(s):  
A. Rita Carrasco ◽  
Katerina Kombiadou ◽  
Miguel Amado
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Salt Marshes ◽  
Anthropogenic Pressures ◽  
The Past ◽  
Ria Formosa ◽  
Sediment Loads ◽  
Human Interventions ◽  
South Portugal ◽  
And Sea Level

<p>It is predictable that salt marshes in regions, where sediment loads are high, should be stable against a broader range of relative sea level scenarios than those in sediment-poor systems. Despite extensive theoretical and laboratory studies, additional syntheses of marsh ‘persistence’ indicators under human interventions and accelerated sea-level rise rates are still needed. This study investigates the recent lateral changes occurring in lagoon-type marshes of the Ria Formosa lagoon (south Portugal) in the presence of human interventions and sea-level rise, to identify the major drivers for past marsh evolution and to estimate potential future trends. The conducted analysis assessed the past geomorphological adjustment based on imagery analysis and assessed its potential future adjustment to sea-level rise (~100 years) based on modelled land cover changes (by employing the SLAMM model within two sea-level rise scenarios).</p><p>Salt marshes in the Ria Formosa showed slow lateral growth rates over the last 70 years (<1 mm∙yr<sup>-1</sup>), with localized erosion along the main navigable channels associated with dredging activities. Higher change rates were noted near the inlets, with stronger progradation near the natural inlets of the system, fed by sediment influx pulses. Any potential influence of sea-level increase to an intensification of marsh-edge erosion in the past, could not be distinguished from human-induced pressures in the area. No significant sediment was exchanged between the salt marshes and tidal flats, and no self-organization pattern between them was observed in past. The related analysis showed that landcover changes in the salt marsh areas are likely to be more prominent in the future. The obtained results showed evidence of non-linearity in marsh response to high sea-level rise rates, which could indicate to the presence of critical thresholds and potential negative feedbacks within the system, with significant implications to marsh resilience.</p>

scholarly journals Significant total mass contained in small glaciers

2012 ◽  
Vol 6 (1) ◽  
pp. 737-757
Author(s):  
D. B. Bahr ◽  
V. Radić
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Total Mass ◽  
Complete List ◽  
Ice Caps ◽  
Ice Volume ◽  
Regional Estimates ◽  
Source Of Error

Abstract. A single large glacier can contain hundreds of millions of times the mass of a small glacier. Nevertheless, small glaciers are so numerous that their contribution to the world's total ice volume is significant and may be a notable source of error if excluded. With current glacier inventories, total volume errors on the order of 10 % are possible at both global and regional scales. However, errors of less than 1 % require glaciers that are smaller than those available in some inventories. Such accuracy requires a global list of all glaciers and ice caps (GIC) as small as 1 km2, and for regional estimates requires substantially smaller sizes. For some regions, volume errors of less than 5 % require a complete list of all glaciers down to the smallest conceivable sizes. For this reason, sea-level rise estimates and other total mass and total volume analyses cannot ignore the world's smallest glaciers without careful justification.

scholarly journals TSUNAMI RISK ASSESSMENT MODELLING IN CHABAHAR PORT, IRAN

2017 ◽  
Vol XLII-2/W7 ◽  
pp. 461-467
Author(s):  
M. R. Delavar ◽  
H. Mohammadi ◽  
M. A. Sharifi ◽  
M. D. Pirooz
Keyword(s):  
Risk Assessment ◽  
Sea Level ◽  
Western India ◽  
Case Scenario ◽  
Worst Case ◽  
Dry Land ◽  
Great Loss ◽  
Makran Subduction Zone ◽  
Tsunami Waves ◽  
Historical Tsunami

The well-known historical tsunami in the Makran Subduction Zone (MSZ) region was generated by the earthquake of November 28, 1945 in Makran Coast in the North of Oman Sea. This destructive tsunami killed over 4,000 people in Southern Pakistan and India, caused great loss of life and devastation along the coasts of Western India, Iran and Oman. According to the report of "Remembering the 1945 Makran Tsunami", compiled by the Intergovernmental Oceanographic Commission (UNESCO/IOC), the maximum inundation of Chabahar port was 367 m toward the dry land, which had a height of 3.6 meters from the sea level. In addition, the maximum amount of inundation at Pasni (Pakistan) reached to 3 km from the coastline. For the two beaches of Gujarat (India) and Oman the maximum run-up height was 3 m from the sea level. In this paper, we first use Makran 1945 seismic parameters to simulate the tsunami in generation, propagation and inundation phases. The effect of tsunami on Chabahar port is simulated using the ComMIT model which is based on the Method of Splitting Tsunami (MOST). In this process the results are compared with the documented eyewitnesses and some reports from researchers for calibration and validation of the result. Next we have used the model to perform risk assessment for Chabahar port in the south of Iran with the worst case scenario of the tsunami. The simulated results showed that the tsunami waves will reach Chabahar coastline 11 minutes after generation and 9 minutes later, over 9.4 Km<sup>2</sup> of the dry land will be flooded with maximum wave amplitude reaching up to 30 meters.

scholarly journals Exceptional retreat of Novaya Zemlya's marine-terminating outlet glaciers between 2000 and 2013

2017 ◽  
Author(s):  
J. Rachel Carr ◽  
Heather Bell ◽  
Rebecca Killick ◽  
Tom Holt
Keyword(s):  
Sea Ice ◽  
Sea Level Rise ◽  
Sea Level ◽  
Remotely Sensed ◽  
Glacier Retreat ◽  
Remotely Sensed Data ◽  
Novaya Zemlya ◽  
The Past ◽  
Air Temperatures ◽  
The Impact

Abstract. Novaya Zemlya (NVZ) has experienced rapid ice loss and accelerated marine-terminating glacier retreat during the past two decades. However, it is unknown whether this retreat is exceptional longer-term and/or whether it has persisted since 2010. Investigating this is vital, as dynamic thinning may contribute substantially to ice loss from NVZ, but is not currently included in sea level rise predictions. Here, we use remotely sensed data to assess controls on NVZ glacier retreat between the 1973/6 and 2015. Glaciers that terminate into lakes or the ocean receded 3.5 times faster than those that terminate on land. Between 2000 and 2013, retreat rates were significantly higher on marine-terminating outlet glaciers than during the previous 27 years, and we observe widespread slow-down in retreat, and even advance, between 2013 and 2015. There were some common patterns in the timing of glacier retreat, but the magnitude varied between individual glaciers. Rapid retreat between 2000–2013 corresponds to a period of significantly warmer air temperatures and reduced sea ice concentrations, and to changes in the NAO and AMO. We need to assess the impact of this accelerated retreat on dynamic ice losses from NVZ, to accurately quantify its future sea level rise contribution.

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