Search results for: when-the-sahara-was-green

When the Sahara Was Green

Author : Martin Williams
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The little-known history of how the Sahara was transformed from a green and fertile land into the largest hot desert in the world The Sahara is the largest hot desert in the world, equal in size to China or the United States. Yet, this arid expanse was once a verdant, pleasant land, fed by rivers and lakes. The Sahara sustained abundant plant and animal life, such as Nile perch, turtles, crocodiles, and hippos, and attracted prehistoric hunters and herders. What transformed this land of lakes into a sea of sands? When the Sahara Was Green describes the remarkable history of Earth’s greatest desert—including why its climate changed, the impact this had on human populations, and how scientists uncovered the evidence for these extraordinary events. From the Sahara’s origins as savanna woodland and grassland to its current arid incarnation, Martin Williams takes us on a vivid journey through time. He describes how the desert’s ancient rocks were first fashioned, how dinosaurs roamed freely across the land, and how it was later covered in tall trees. Along the way, Williams addresses many questions: Why was the Sahara previously much wetter, and will it be so again? Did humans contribute to its desertification? What was the impact of extreme climatic episodes—such as prolonged droughts—upon the Sahara’s geology, ecology, and inhabitants? Williams also shows how plants, animals, and humans have adapted to the Sahara and what lessons we might learn for living in harmony with the harshest, driest conditions in an ever-changing global environment. A valuable look at how an iconic region has changed over millions of years, When the Sahara Was Green reveals the desert’s surprising past to reflect on its present, as well as its possible future.

Revive Eden

Author : Hong-Quan Zhang
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Atlantis is not hiding at the bottom of the Atlantic Ocean but in plain view on top of the Sahara Desert. The prosperity of the Atlas Empire and the inundation of Atlantis corresponded to a lush Green Sahara started around 12,000 years ago. About 5700 years ago, the Green Sahara suddenly began to wither from the Atlas Basin, the heartland of the Atlas Empire. This is the rain shadow area of the Atlas Mountain range in today's Northeast Algeria and South Tunisia. When the water cycle stability in this standalone catchment was broken, the Chotts Megalakes (the Atlantic Sea) dried rapidly and the strong rain shadow effect of the Atlas Mountain became fully active. Deserts formed immediately in this area and gradually expanded east and south, like a spreading wildfire powered by the prevailing winds. This led to desertification and aridification in North Africa, West Asia, and the Mediterranean synchronously until this day. This timeline spans most of human history as we know it, including the thriving and dispersion of Atlas Empire, the rise and fall of Egypt, the prosperity and desolation of Mesopotamia, and the civilization shifts first from west to east and then from east to west across the Mediterranean and the Atlantic. The Atlantic Sea had a surface area over 26,000 sq km, which generated a great amount of water vapor, sufficient to eliminate the strong rain shadow effect of the Atlas Mountain, so that the Green Sahara was stabilized for about six thousand years. The Earth's precession (wobbling) has been blamed as the main control for the flipping between desert and green in the Sahara. This view has misled the academic society away from seeking the true primary cause for so long. The water cycle stability of the Sahara is governed by the non-linear relationship between precipitation and evaporation, which depends on surface conditions and atmospheric circulation. The Earth's precession only moved the water cycle closer to its unstable point so that a perturbation could trigger the transition from wet to dry state. This book explains the start and step-by-step spread of the Sahara Desert and its impact on West Asia and the Mediterranean regions. Archaeological records and paleoclimate data corroborate this new insight of the Sahara expansion process and the consequential desertification in these areas. The desertification process in Northwest China is an independent validation for the same control mechanism. Based on the new understanding, approaches are suggested to revive the Northwest China ecosystem, to turn the Sahara back to green and to ameliorate Australia to a water abundant country.

Gdy Sahara by a zielona

Author : Marek Chłodnicki
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Challenges of a Changing Earth

Author : Will Steffen
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This volume is based on plenary presentations from Challenges of a Changing Earth, a Global Change Open Science Conference held in Amsterdam, The Neth- lands, in July 2001. The meeting brought together about 1400 scientists from 105 co- tries around the world to describe, discuss and debate the latest scientific - derstanding of natural and human-driven changes to our planet. It examined the effects of these changes on our societies and our lives, and explored what the future might hold. The presentations drew upon global change science from an exceptionally wide range of disciplines and approaches. Issues of societal importance – the food system, air quality, the carbon cycle, and water resources – were highlighted from both policy and science perspectives. Many of the talks presented the exciting scientific advances of the past decade of international research on global change. Several challenged the scientific community in the future. What are the visionary and creative new approaches needed for studying a complex planetary system in which human activities are in- mately interwoven with natural processes? This volume aims to capture the timeliness and excitement of the science p- sented in Amsterdam. The plenary speakers were given a daunting task: to reproduce their presentations in a way that delivers their scientific messages accurately and in sufficient detail but at the same time reaches a very broad audience well beyond their own disciplines. Furthermore, they were required to do this in just a few pages.

A Numerical Study on the Green Sahara During the Mid Holocene

Author : Minoru Chikira
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Aspects of Nature in the African Sahara

Author : Angelo Heilprin
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-Aspects of Nature in the African Sahara- "With all the wild, fitful, and forbidding Nature that belongs to the Sahara, it has also its elements of peace and good will. The cheer of a green oasis is, indeed, one of its first greetings, and long before the great flat expanse of sand is reached the traveler approaching from the north looks down upon an island of emerald verdure."

Climate Change in Human History

Author : Benjamin Lieberman
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Climate Change and Human History provides a concise introduction to the relationship between human beings and climate change throughout history. Starting hundreds of thousands of years ago and going up to the present day, this book illustrates how natural climate variability affected early human societies and how human activity is now leading to drastic changes to our climate. Taking a chronological approach the authors explain how climate change created opportunities and challenges for human societies in each major time period, covering themes such as phases of climate and history, climate shocks, the rise and fall of civilizations, industrialization, accelerating climate change and our future outlook. This 2nd edition includes a new chapter on the explosion of social movements, protest groups and key individuals since 2017 and the implications this has had on the history of climate change, an improved introduction to the Anthropocene and extra content on the basic dynamics of the climate system alongside updated historiography. With more case studies, images and individuals throughout the text, the second edition also includes a glossary of terms and further reading to aid students in understanding this interdisciplinary subject. An ideal companion for all students of environmental history, Climate Change and Human History clearly demonstrates the critical role of climate in shaping human history and of the experience of humans in both adapting to and shaping climate change.

Biodiversity Conservation and Environmental Change

Author : Lindsey Gillson
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Ecosystems today are dynamic and complex, leaving conservationists faced with the paradox of conserving moving targets. New approaches to conservation are now required that aim to conserve ecological function and process, rather than attempt to protect static snapshots of biodiversity. To do this effectively, long-term information on ecosystem variability and resilience is needed. While there is a wealth of such information in palaeoecology, archaeology, and historical ecology, it remains an underused resource by conservation ecologists. In bringing together the disciplines of neo- and palaeoecology and integrating them with conservation biology, this novel text illustrates how an understanding of long-term change in ecosystems can in turn inform and influence their conservation and management in the Anthropocene. By looking at the history of traditional management, climate change, disturbance, and land-use, the book describes how a long-term perspective on landscape change can inform current and pressing conservation questions such as whether elephants should be culled, how best to manage fire, and whether ecosystems can or should be "re-wilded" Biodiversity Conservation and Environmental Change is suitable for senior undergraduate and post-graduate students in conservation ecology, palaeoecology, biodiversity conservation, landscape ecology, environmental change and natural resource management. It will also be of relevance and use to a global market of conservation practitioners, researchers, educators and policy-makers.

Writing is the Word

Author : Jimi Rand
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Desert animals in the eastern Sahara status economic significance and cultural reflection in antiquity

Author : Heiko Riemer
File Size : 87.28 MB
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