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1. Simplicity Amid Complexity

Author:
Isaac Held
Source:
Science 2014 v.343 no.6176 pp. 1206-1207
ISSN:
0036-8075
Subject:
aerosols; climate; humans; methane; prediction; uncertainty; weather
Abstract:
... We live in interesting times as we watch diverse effects of human activities on Earth's climate emerge from natural variability. In predicting the outcome of this evolving inadvertent experiment, climate science faces many challenges, some of which have been outlined in this series of Science Perspectives (1 – 6): reducing the uncertainty in climate sensitivity; explaining the recent slowdown in t ...
DOI:
10.1126/science.1248447

2. Dust Unto Dust

Author:
Mary C. Scholes; Robert J. Scholes
Source:
Science 2013 v.342 no.6158 pp. 565-566
ISSN:
0036-8075
Subject:
climate; fertilizers; humans; irrigation; prairie soils; salinity; soil biota; soil ecosystems; soil erosion; Africa
Abstract:
... In the past, great civilizations have fallen because they failed to prevent the degradation of the soils on which they were founded (1). The modern world could suffer the same fate at a global scale. The inherent productivity of many lands has been dramatically reduced as a result of soil erosion, accumulation of salinity, and nutrient depletion. In Africa, where much of the future growth in agric ...
DOI:
10.1126/science.1244579

3. Opportunities and Challenges in Next Generation Standards

Author:
E. K. Stage; H. Asturias; T. Cheuk; P. A. Daro; S. B. Hampton
Source:
Science 2013 v.340 no.6130 pp. 276-277
ISSN:
0036-8075
Subject:
climate; humans; models; people; science education; secondary education; United States
Abstract:
... Imagine that politicians and the people they represent understood how human activity impacts Earth, including climate. And imagine that they had learned how to evaluate claims, argue from evidence, and understand models. These understandings and practices are prominent in the U.S. National Research Council (NRC) framework to guide the next iteration of standards for U.S. elementary and secondary s ...
DOI:
10.1126/science.1234011

4. Quantifying the Influence of Climate on Human Conflict

Author:
Solomon M. Hsiang; Marshall Burke; Edward Miguel
Source:
Science 2013 v.341 no.6151 pp. 1235367
ISSN:
0036-8075
Subject:
archaeology; climate; humans; meta-analysis; psychology; rain; temperature; violence
Abstract:
... Climate and Conflict Knowledge silos can hinder attempts to explore questions of interest across many disciplines. Hsiang et al. (p. 1235367 , published online 1 August) provide a meta-analysis of data from disciplines as disparate as archaeology and psychology to examine the relation between climate and conflict. Overall, warmer temperatures or extremes of rainfall can be causally associated with ...
DOI:
10.1126/science.1235367

5. The Aftermath of Megafaunal Extinction: Ecosystem Transformation in Pleistocene Australia

Author:
Susan Rule; Barry W. Brook; Simon G. Haberle; Chris S. M. Turney; A. Peter Kershaw; Christopher N. Johnson
Source:
Science 2012 v.335 no.6075 pp. 1483-1486
ISSN:
0036-8075
Subject:
anthropogenic activities; climate; climate change; ecosystems; environmental impact; extinction; fauna; herbivores; humans; landscapes; rain forests; wildfires; Australia
Abstract:
... Giant vertebrates dominated many Pleistocene ecosystems. Many were herbivores, and their sudden extinction in prehistory could have had large ecological impacts. We used a high-resolution 130,000-year environmental record to help resolve the cause and reconstruct the ecological consequences of extinction of Australia’s megafauna. Our results suggest that human arrival rather than climate caused me ...
DOI:
10.1126/science.1214261

6. Intensifying Weathering and Land Use in Iron Age Central Africa

Author:
Germain Bayon; Bernard Dennielou; Joël Etoubleau; Emmanuel Ponzevera; Samuel Toucanne; Sylvain Bermell
Source:
Science 2012 v.335 no.6073 pp. 1219-1222
ISSN:
0036-8075
Subject:
climate; climate change; farmers; humans; land use; marine sediments; rain forests; savannas; trees; weathering; Central Africa
Abstract:
... About 3000 years ago, a major vegetation change occurred in Central Africa, when rainforest trees were abruptly replaced by savannas. Up to this point, the consensus of the scientific community has been that the forest disturbance was caused by climate change. We show here that chemical weathering in Central Africa, reconstructed from geochemical analyses of a marine sediment core, intensified abr ...
DOI:
10.1126/science.1215400

7. Response to Comments on “Intensifying Weathering and Land Use in Iron Age Central Africa”

Author:
Germain Bayon; Bernard Dennielou; Joël Etoubleau; Emmanuel Ponzevera; Samuel Toucanne; Sylvain Bermell
Source:
Science 2012 v.337 no.6098 pp. 1040
ISSN:
0036-8075
Subject:
climate; humans; land use; rain forests; weathering; Central Africa
Abstract:
... Neumann et al . argue that terrestrial evidence does not support our interpretation of large-scale human land use in Central Africa about 2500 years ago and that climate was the main driver of the rainforest crisis at that time, and Maley et al . raise a number of concerns about our interpretation of data from chemical weathering proxies. Taking into account existing palaeoclimatic data and clarif ...
DOI:
10.1126/science.1221747
PubMed:
22936758
PubMed Central:
PMC3556809

8. 2500 Years of European Climate Variability and Human Susceptibility

Author:
Büntgen, Ulf; Tegel, Willy; Nicolussi, Kurt; McCormick, Michael; Frank, David; Trouet, Valerie; Kaplan, Jed O.; Herzig, Franz; Heussner, Karl-Uwe; Wanner, Heinz; Luterbacher, Jürg; Esper, Jan
Source:
Science 2011 v.331 no.6017 pp. 578-582
ISSN:
0036-8075
Subject:
anthropogenic activities; climate; climate change; humans; politics; risk; summer; temperature
Abstract:
... Climate variations influenced the agricultural productivity, health risk, and conflict level of preindustrial societies. Discrimination between environmental and anthropogenic impacts on past civilizations, however, remains difficult because of the paucity of high-resolution paleoclimatic evidence. We present tree ring-based reconstructions of central European summer precipitation and temperature ...
DOI:
10.1126/science.1197175

9. Fire in the Earth System

Author:
Bowman, David M.J.S.; Balch, Jennifer K.; Artaxo, Paulo; Bond, William J.; Carlson, Jean M.; Cochrane, Mark A.; D'Antonio, Carla M.; DeFries, Ruth S.; Doyle, John C.; Harrison, Sandy P.; Johnston, Fay H.; Keeley, Jon E.; Krawchuk, Meg A.; Kull, Christian A.; Marston, J. Brad; Moritz, Max A.; Prentice, I. Colin; Roos, Christopher I.; Scott, Andrew C.; Swetnam, Thomas W.; van der Werf, Guido R.; Pyne, Stephen J.
Source:
Science 2009 v.324 no.5926 pp. 481-484
ISSN:
0036-8075
Subject:
carbon cycle; climate; climate change; ecosystems; fire regime; fires; humans; models; plants (botany); risk; vegetation
Abstract:
... Fire is a worldwide phenomenon that appears in the geological record soon after the appearance of terrestrial plants. Fire influences global ecosystem patterns and processes, including vegetation distribution and structure, the carbon cycle, and climate. Although humans and fire have always coexisted, our capacity to manage fire remains imperfect and may become more difficult in the future as clim ...
DOI:
10.1126/science.1163886

10. A Combined Mitigation/Geoengineering Approach to Climate Stabilization

Author:
Wigley, T.M.L.
Source:
Science 2006 v.314 no.5798 pp. 452-454
ISSN:
0036-8075
Subject:
acidity; aerosols; carbon dioxide; climate; climate change; environmental engineering; fossil fuels; greenhouse gas emissions; humans; oceans; stratosphere; sulfates
Abstract:
... Projected anthropogenic warming and increases in CO₂ concentration present a twofold threat, both from climate changes and from CO₂ directly through increasing the acidity of the oceans. Future climate change may be reduced through mitigation (reductions in greenhouse gas emissions) or through geoengineering. Most geoengineering approaches, however, do not address the problem of increasing ocean a ...
DOI:
10.1126/science.1131728

11. Global Hydrological Cycles and World Water Resources

Author:
Oki, Taikan; Kanae, Shinjiro
Source:
Science 2006 v.313 no.5790 pp. 1068-1072
ISSN:
0036-8075
Subject:
climate; climate change; freshwater; humans; hydrologic cycle; people; probability; seasonal variation; society; water resources; water stress
Abstract:
... Water is a naturally circulating resource that is constantly recharged. Therefore, even though the stocks of water in natural and artificial reservoirs are helpful to increase the available water resources for human society, the flow of water should be the main focus in water resources assessments. The climate system puts an upper limit on the circulation rate of available renewable freshwater res ...
DOI:
10.1126/science.1128845

12. The mtDNA Legacy of the Levantine Early Upper Palaeolithic in Africa

Author:
Olivieri, Anna; Achilli, Alessandro; Pala, Maria; Battaglia, Vincenza; Fornarino, Simona; Al-Zahery, Nadia; Scozzari, Rosaria; Cruciani, Fulvio; Behar, Doron M.; Dugoujon, Jean-Michel; Coudray, Clotilde; Santachiara-Benerecetti, A. Silvana; Semino, Ornella; Bandelt, Hans-Jürgen; Torroni, Antonio
Source:
Science 2006 v.314 no.5806 pp. 1767-1770
ISSN:
0036-8075
Subject:
climate; humans; industry; mitochondria; mitochondrial DNA; Asia; Europe; Mediterranean region; Northern Africa
Abstract:
... Sequencing of 81 entire human mitochondrial DNAs (mtDNAs) belonging to haplogroups M1 and U6 reveals that these predominantly North African clades arose in southwestern Asia and moved together to Africa about 40,000 to 45,000 years ago. Their arrival temporally overlaps with the event(s) that led to the peopling of Europe by modern humans and was most likely the result of the same change in climat ...
DOI:
10.1126/science.1135566

13. From Dimming to Brightening: Decadal Changes in Solar Radiation at Earth's Surface

Author:
Wild, Martin; Gilgen, Hans; Roesch, Andreas; Ohmura, Atsumu; Long, Charles N.; Dutton, Ellsworth G.; Forgan, Bruce; Kallis, Ain; Russak, Viivi; Tsvetkov, Anatoly
Source:
Science 2005 v.308 no.5723 pp. 847-850
ISSN:
0036-8075
Subject:
climate; ecosystems; glaciers; humans; hydrologic cycle; solar radiation
Abstract:
... Variations in solar radiation incident at Earth's surface profoundly affect the human and terrestrial environment. A decline in solar radiation at land surfaces has become apparent in many observational records up to 1990, a phenomenon known as global dimming. Newly available surface observations from 1990 to the present, primarily from the Northern Hemisphere, show that the dimming did not persis ...
DOI:
10.1126/science.1103215

14. Global Iron Connections Between Desert Dust, Ocean Biogeochemistry, and Climate

Author:
Jickells, T. D.; An, Z. S.; Andersen, K. K.; Baker, A. R.; Bergametti, G.; Brooks, N.; Cao, J. J.; Boyd, P. W.; Duce, R. A.; Hunter, K. A.; Kawahata, H.; Kubilay, N.; laRoche, J.; Liss, P. S.; Mahowald, N.; Prospero, J. M.; Ridgwell, A. J.; Tegen, I.; Torres, R.
Source:
Science 2005 v.308 no.5718 pp. 67-71
ISSN:
0036-8075
Subject:
Earth system science; biogeochemistry; climate; dust; energy; environmental factors; humans; iron; oceans; soil; uncertainty
Abstract:
... The environmental conditions of Earth, including the climate, are determined by physical, chemical, biological, and human interactions that transform and transport materials and energy. This is the "Earth system": a highly complex entity characterized by multiple nonlinear responses and thresholds, with linkages between disparate components. One important part of this system is the iron cycle, in ...
DOI:
10.1126/science.1105959

15. Penetration of Human-Induced Warming into the World's Oceans

Author:
Barnett, Tim P.; Pierce, David W.; AchutaRao, Krishna M.; Gleckler, Peter J.; Santer, Benjamin D.; Gregory, Jonathan M.; Washington, Warren M.
Source:
Science 2005 v.309 no.5732 pp. 284-287
ISSN:
0036-8075
Subject:
advection; climate; climate change; climate models; humans; oceans; prediction; society
Abstract:
... A warming signal has penetrated into the world's oceans over the past 40 years. The signal is complex, with a vertical structure that varies widely by ocean; it cannot be explained by natural internal climate variability or solar and volcanic forcing, but is well simulated by two anthropogenically forced climate models. We conclude that it is of human origin, a conclusion robust to observational s ...
DOI:
10.1126/science.1112418