A Stable or an Unstable World?

On Gaia ◽  
2013 ◽  
Author(s):  
Toby Tyrrell
Keyword(s):  
Compelling Evidence ◽  
Earth History ◽  
Gaia Hypothesis ◽  
The Earth ◽  
Constant Environment ◽  
Earth Environment ◽  
Life On Earth

This chapter examines the claim of Earth's stability by looking at data pertaining to past variability of the Earth environment. The Gaia hypothesis proposes that life has had a hand on the tiller of Earth climate, ensuring stable equable climates throughout Earth history. The chapter argues differently. The data do not point to a constant environment, or to a cozy and hospitable one. In addition to the overall trend toward ever-icier climates over the last 100 million years, there is also compelling evidence that the tiller has on other occasions allowed climate to drift into dangerous states threatening to completely extinguish all life on Earth.

scholarly journals Life on Earth is hard to spot

2020 ◽  
Vol 7 (3) ◽  
pp. 248-272
Author(s):  
Timothy M Lenton ◽  
Sébastien Dutreuil ◽  
Bruno Latour
Keyword(s):  
Energy Balance ◽  
Earth System ◽  
Gaia Hypothesis ◽  
The Earth ◽  
Life On Earth

The triumph of the Gaia hypothesis was to spot the extraordinary influence of Life on the Earth. ‘Life’ is the clade including all extant living beings, as distinct from ‘life’ the class of properties common to all living beings. ‘Gaia’ is Life plus its effects on habitability. Life’s influence on the Earth was hard to spot for several reasons: biologists missed it because they focused on life not Life; climatologists missed it because Life is hard to see in the Earth’s energy balance; Earth system scientists opted instead for abiotic or human-centred approaches to the Earth system; Scientists in general were repelled by teleological arguments that Life acts to maintain habitable conditions. Instead, we reason from organisms’ metabolisms outwards, showing how Life’s coupling to its environment has led to profound effects on Earth’s habitability. Recognising Life’s impact on Earth and learning from it could be critical to understanding and successfully navigating the Anthropocene.

LITTLE ICE AGE IN THE EARTH HISTORY AND ITS POSSIBLE REASONS

2020 ◽  
Vol 42 (1) ◽  
pp. 4-12
Author(s):  
Valeriy Fedorov ◽  
Denis Frolov
Keyword(s):  
Little Ice Age ◽  
Ice Age ◽  
Earth History ◽  
The Earth

scholarly journals Onboard Radio Frequency Interference as the Origin of Inter-Satellite Biases for Microwave Humidity Sounders

2019 ◽  
Vol 11 (7) ◽  
pp. 866 ◽  
Author(s):  
Imke Hans ◽  
Martin Burgdorf ◽  
Stefan A. Buehler
Keyword(s):  
Time Series ◽  
Radio Frequency ◽  
Time Dependent ◽  
Radio Frequency Interference ◽  
Climate Variables ◽  
Compelling Evidence ◽  
Climate Data ◽  
The Earth ◽  
Correction Scheme

Understanding the causes of inter-satellite biases in climate data records from observations of the Earth is crucial for constructing a consistent time series of the essential climate variables. In this article, we analyse the strong scan- and time-dependent biases observed for the microwave humidity sounders on board the NOAA-16 and NOAA-19 satellites. We find compelling evidence that radio frequency interference (RFI) is the cause of the biases. We also devise a correction scheme for the raw count signals for the instruments to mitigate the effect of RFI. Our results show that the RFI-corrected, recalibrated data exhibit distinctly reduced biases and provide consistent time series.

Environmentally Responsible Behaviour for a Sustainable Future

2021 ◽  
Vol 10 (1) ◽  
pp. 21-27
Author(s):  
Rasna Sehrawat ◽  
◽  
Anshu Mathur
Keyword(s):  
Biological Diversity ◽  
Earth Systems ◽  
Responsible Behavior ◽  
Environmental Deterioration ◽  
The Earth ◽  
Environmentally Responsible ◽  
Ecological Culture ◽  
The Individual ◽  
Life On Earth ◽  
Threat To Life

Humans are the only species on the planet Earth who do not contribute in the natural environmental cycle but has always been the exploiter of the limited resources. Tecer (2007) told that Environmental deterioration, extinction, or pollution in many vital earth systems, such as air, water, soil, forest, and biological diversity have required countries to develop policies for protecting and developing the earth and promoting global cooperation on these issues. Atasoy (2005) concluded in his study that Environmental problems have become globalized and have reached the stage where they present a threat to life on Earth. This situation has led to the review of people's relationships with nature, their attitudes and behaviors towards the environment, the duties and responsibilities assumed by the individual towards nature, and the redefinition of ecological culture and environmental awareness. It is imperative to be Environmentally Responsible in the present scenario where awareness on the effect of responsible behavior already exists in abundance through media, curriculum, and social activities.

Sunspot and Group Number: Recent advances from historical data

2018 ◽  
Vol 14 (A30) ◽  
pp. 156-159 ◽  
Author(s):  
Frédéric Clette ◽  
José M. Vaquero ◽  
María Cruz Gallego ◽  
Laure Lefèvre
Keyword(s):  
Sunspot Number ◽  
Maunder Minimum ◽  
Current Data ◽  
Activity Level ◽  
Historical Evidence ◽  
The Earth ◽  
Earth Environment ◽  
Group Number ◽  
Dalton Minimum

AbstractDue to its unique 400-year duration, the sunspot number is a central reference for understanding the long-term evolution of solar activity and its influence on the Earth environment and climate. Here, we outline current data recovery work. For the sunspot number, we find historical evidence of a disruption in the source observers occurring in 1947–48. For the sunpot group number, recent data confirm the clear southern predominance of sunspots during the Maunder Minimum, while the umbra-penumbra ratio is similar to other epochs. For the Dalton minimum, newly recovered historical observations confirm a higher activity level than in a true Grand Minimum.

scholarly journals Towards understanding how surface life can affect interior geological processes: a non-equilibrium thermodynamics approach

2011 ◽  
Vol 2 (1) ◽  
pp. 139-160 ◽  
Author(s):  
J. G. Dyke ◽  
F. Gans ◽  
A. Kleidon
Keyword(s):  
Continental Crust ◽  
Oceanic Crust ◽  
Mantle Convection ◽  
Dynamical Models ◽  
Geological Processes ◽  
The Earth ◽  
Uplift And Erosion ◽  
Life On Earth ◽  
Mantle Temperature ◽  
Non Equilibrium

Abstract. Life has significantly altered the Earth's atmosphere, oceans and crust. To what extent has it also affected interior geological processes? To address this question, three models of geological processes are formulated: mantle convection, continental crust uplift and erosion and oceanic crust recycling. These processes are characterised as non-equilibrium thermodynamic systems. Their states of disequilibrium are maintained by the power generated from the dissipation of energy from the interior of the Earth. Altering the thickness of continental crust via weathering and erosion affects the upper mantle temperature which leads to changes in rates of oceanic crust recycling and consequently rates of outgassing of carbon dioxide into the atmosphere. Estimates for the power generated by various elements in the Earth system are shown. This includes, inter alia, surface life generation of 264 TW of power, much greater than those of geological processes such as mantle convection at 12 TW. This high power results from life's ability to harvest energy directly from the sun. Life need only utilise a small fraction of the generated free chemical energy for geochemical transformations at the surface, such as affecting rates of weathering and erosion of continental rocks, in order to affect interior, geological processes. Consequently when assessing the effects of life on Earth, and potentially any planet with a significant biosphere, dynamical models may be required that better capture the coupled nature of biologically-mediated surface and interior processes.

“A Life Worthy of Being Called Human”

2019 ◽  
Vol 41 (4) ◽  
pp. 319-332
Author(s):  
Catherine Larrère ◽  
Keyword(s):  
Sustainable Development ◽  
Human Life ◽  
Environmental Ethic ◽  
Future Generations ◽  
Human Beings ◽  
Second Stage ◽  
Making Sense ◽  
The Earth ◽  
Life On Earth ◽  
Ecological Transition

“Act so that the effects of your action are compatible with the permanence of genuine human life on Earth.” How can we understand Jonas’ “maxim”? Is it too anthropocentric to be of any interest for an environmental ethic? Is is too limited to survival to have a moral signification in a truly human ethic? One can argue first that it is not so much anti-Kantian than that it challenges the current prevailing “presentism” and obliges us to take into consideration not only future generations, but also the context in which one anticipates these future generations to be living. Therefore, we can distinguish two different interpretations of Jonas’ maxim: in a first stage, that of sustainable development, it was understood as taking into consideration not only the needs but also the rights of future generations; in a second stage, that of an Anthropocene and ecological transition, it means that making sense of humanity implies connecting human beings to the Earth and other living beings far from opposing them.

scholarly journals Jupiter – friend or foe? II: the Centaurs

2008 ◽  
Vol 8 (2) ◽  
pp. 75-80 ◽  
Author(s):  
J. Horner ◽  
B.W. Jones
Keyword(s):  
Solar System ◽  
Kuiper Belt ◽  
Giant Planet ◽  
Mass Extinctions ◽  
The Earth ◽  
Impact Rate ◽  
Short Period ◽  
Impact Risk ◽  
Life On Earth ◽  
The Impact

AbstractIt has long been assumed that the planet Jupiter acts as a giant shield, significantly lowering the impact rate of minor bodies upon the Earth, and thus enabling the development and evolution of life in a collisional environment which is not overly hostile. In other words, it is thought that, thanks to Jupiter, mass extinctions have been sufficiently infrequent that the biosphere has been able to diversify and prosper. However, in the past, little work has been carried out to examine the validity of this idea. In the second of a series of papers, we examine the degree to which the impact risk resulting from objects on Centaur-like orbits is affected by the presence of a giant planet, in an attempt to fully understand the impact regime under which life on Earth has developed. The Centaurs are a population of ice-rich bodies which move on dynamically unstable orbits in the outer Solar system. The largest Centaurs known are several hundred kilometres in diameter, and it is certain that a great number of kilometre or sub-kilometre sized Centaurs still await discovery. These objects move on orbits which bring them closer to the Sun than Neptune, although they remain beyond the orbit of Jupiter at all times, and have their origins in the vast reservoir of debris known as the Edgeworth–Kuiper belt that extends beyond Neptune. Over time, the giant planets perturb the Centaurs, sending a significant fraction into the inner Solar System where they become visible as short-period comets. In this work, we obtain results which show that the presence of a giant planet can act to significantly change the impact rate of short-period comets on the Earth, and that such planets often actually increase the impact flux greatly over that which would be expected were a giant planet not present.

Sign in / Sign up

Export Citation Format

Share Document