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Evidence

Evidence
The Earth's climate has changed throughout history. Just in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7,000 years ago marking the beginning of the modern climate era — and of human civilization. Most of these climate changes are attributed to very small variations in Earth’s orbit that change the amount of solar energy our planet receives. Scientific evidence for warming of the climate system is unequivocal. The current warming trend is of particular significance because most of it is very likely human-induced and proceeding at a rate that is unprecedented in the past 1,300 years.1 Earth-orbiting satellites and other technological advances have enabled scientists to see the big picture, collecting many different types of information about our planet and its climate on a global scale. The evidence for rapid climate change is compelling: Sea level rise Global temperature rise Warming oceans Glacial retreat Related:  Climate ChangeClimate Crisis

Understanding the Link Between Climate Change and Extreme Weather | Climate Change Science | US EPA On This Page: Changes in Extreme Weather and Climate Events Scientists study many aspects of change in extreme weather and climate events. These include: Frequency: Are events occurring more often than they did in the past? Intensity: Are events getting more severe, with the potential for more damaging effects? Extreme weather is typically rare. Establishing the most likely causes behind an extreme weather event can be challenging, since these events are due to combinations of multiple factors, including natural variability. There have been changes in some types of extreme weather events in the United States over the last several decades, including more intense and frequent heat waves, less frequent and intense cold waves, and regional changes in floods, droughts, and wildfires.[1] This rise in extreme weather events fits a pattern you can expect with a warming planet. Trends in Specific Extreme Weather Events Learn more by clicking on each tab below: Heat Waves Why does it matter? Droughts

RealClimate: Recent global warming trends: significant or paused or what? Can Nitrogen Be Used to Combat Climate Change? LANSING, Mich.—After more than a decade of research, a team of scientists has found that by releasing one pollutant into the environment, we might help capture another. Findings from one of the National Science Foundation's longest-running studies show that adding nitrogen to soil prompts northern hardwood forests to absorb more heat-trapping carbon dioxide. As the atmosphere's most abundant element, nitrogen plays a significant role in ecosystems, and one to which scientists and policymakers are paying greater attention. Growing evidence suggests that as humanity pumps more nitrogen into the environment, forests could become bigger carbon sinks and help mitigate climate change. But experts warn that it's a dangerous experiment that could have serious consequences. Nitrogen comes from a vast array of sources: farm fertilizer, car exhaust, factory and power plant emissions. There scientists found that decomposition of twigs and other tree litter slowed. There are major caveats, however.

CO2 sinks - Oceans Carbon dioxide readily dissolves in water and the oceans provide a huge reservoir of carbon. Across the world's oceans there is a continual cycle of equilibration of dissolved carbon dioxide in water with carbon dioxide in the atmosphere. Around 88 thousand million tonnes of carbon is released from the surface of the world's oceans each year, with an annual uptake by the oceans of 90 thousand million tonnes. Consequently, the net uptake of carbon dioxide by oceans is estimated to be approximately 2 thousand million tonnes annually. The carbon dioxide which dissolves in our oceans occurs in three main forms. Human Impact Through increasing global temperatures, via human induced global warming, rising sea temperatures may have significant effects on the oceanic carbon dioxide sink. Potential for control

Two degrees: Will we avoid dangerous climate change? 09 Dec 2014, 11:30Simon Evans Limiting warming to no more than two degrees has become the internationally accepted target for climate policy, as we saw in the first blog of our series of pieces looking at the two degrees limit. Scientists think the risks of climate change increase as temperatures rise. It is a readily understood and useful marker of how we're doing at limiting dangerous climate change that has helped focus minds on the scale of the challenge. So will we manage to limit warming to two degrees above pre-industrial? 1. The world has already warmed by 0.85 degrees celsius above the pre-industrial average and if emissions stay high we're on course for more like three to five degrees by 2100,according to the latest Intergovernmental Panel on Climate Change (IPCC) reports. Broadly speaking, however, scientists say it is still theoretically possible to limit warming to two degrees as long as we stick within a fixed carbon budget. So how big is the budget? 2. 3. 4. 5. 6.

Breathingearth - CO2, birth & death rates by country, simulated real-time Giant iceberg poised to break off from Antarctic shelf | World news A giant iceberg, with an area equivalent to Trinidad and Tobago, is poised to break off from the Antarctic shelf. A thread of just 20km of ice is now preventing the 5,000 sq km mass from floating away, following the sudden expansion last month of a rift that has been steadily growing for more than a decade. The iceberg, which is positioned on the most northern major ice shelf in Antarctica, known as Larsen C, is predicted to be one of the largest 10 break-offs ever recorded. Professor Adrian Luckman, a scientist at Swansea University and leader of the UK’s Midas project, said in a statement: “After a few months of steady, incremental advance since the last event, the rift grew suddenly by a further 18km during the second half of December 2016. Only a final 20km of ice now connects an iceberg one quarter the size of Wales to its parent ice shelf.” “If it doesn’t go in the next few months, I’ll be amazed,” Luckman told BBC News.

Oil Investors at Brink of Losing Trillions of Dollars in Assets. Gore: It's That Road Runner Moment Climate: Now or Never A major threat to fossil fuel companies has suddenly moved from the fringe to center stage with a dramatic announcement by Germany’s biggest power company and an intriguing letter from the Bank of England. A growing minority of investors and regulators are probing the possibility that untapped deposits of oil, gas and coal -- valued at trillions of dollars globally -- could become stranded assets as governments adopt stricter climate change policies. The concept gaining traction from Wall Street to the City of London is simple. A Global Push to Save the Planet With representatives from more than 190 countries gathered to discuss climate rules in Lima, the argument that burning all the world’s known oil, gas and coal reserves would overwhelm the atmosphere is moving beyond the realm of environmental activists. Selling Out Former U.S. Big Oil Energy majors such as Exxon Mobil Corp. George Shultz Gone Solar. Stronger Resolve ‘Overstated Potential’ The industry disagrees.

NASA Earth Observatory : Home Earth warming to climate tipping point, warns study Image copyright AP A warmer world will release vast volumes of carbon into the atmosphere, potentially triggering dangerous climate change, scientists warn. Writing in journal Nature, they project that an increase of 1C (1.8F) will release an additional 55 billion tonnes of carbon into the atmosphere by 2050. This could trigger a "positive feedback" and push the planet's climate system past the point of no-return. Previous assessments have not taken carbon released by soil into account. In their Nature paper, an international team of scientists said that the majority of the Earth's terrestrial store of carbon was in the soil. They warned that as the world warmed, organisms living in the planet's soils would become more active, resulting in more carbon being released into the atmosphere - exacerbating warming. "Using this approach we can get a robust idea of the whole picture. "It is very similar to the way we respire and produce carbon dioxide.

Wissenschaftsgeschichte des Klimawandels Die Forschungsgeschichte des Klimawandels begann im frühen 19. Jahrhundert mit der Feststellung der Eiszeiten und anderer natürlicher Veränderungen im Rahmen der Paläoklimatologie und der Entdeckung des natürlichen Treibhauseffekts im Jahr 1824. Bereits Ende des 19. Jahrhunderts wurden menschliche Einflüsse über Treibhausgase vermutet, entsprechende Berechnungen wurden aber bis in die 1960er Jahre hinein verworfen. Eine Beschreibung der Geschichte der Wissenschaft über insbesondere anthropogene Klimaveränderungen findet sich beispielsweise im 1. Die Betrachtung des Klimawandels, insbesondere die Erkenntnisse zur globalen Erwärmung, sind eng verknüpft mit der Untersuchung der Eiszeiten, und auf der Suche nach den Ursachen für das Kommen und Gehen der Eiszeiten fand man die wahrscheinlichen Ursachen und Mechanismen der menschengemachten globalen Erwärmung. Die Entdeckung der Grundlagen[Bearbeiten] Wissenschaftler, die gegen Ende des 19. und Anfang des 20. Jean Baptiste Fourier[Bearbeiten]

Oil, Water, and Climate: An Introduction: Amazon.fr: Catherine Gautier: Livres anglais et étrangers Fossil fuel firms are still bankrolling climate denial lobby groups | Environment The oil giant BP has announced that they will no longer fund the American Legislative Exchange Council (Alec), a lobbying group that routinely misrepresents climate science to US state legislators. It is the latest sign that some of the world’s largest fossil fuel companies appear to be warming to the overwhelming evidence that the unabated use of their products poses severe risks of disrupting the climate. Last month, BP and Royal Dutch Shell announced their support for shareholder resolutions calling on them to commit to reduce heat-trapping emissions, invest in renewable energy, and show how their current business model would hold up against the strict limits on future emissions needed to limit the risk of major climate disruption. Shell chief executive Ben van Buerden recently stated that “climate change is real and a threat we want to act upon. But appearances can be deceiving. Who will pay these and other costs of preparing for now inevitable changes?

Two degrees? Sounds nice. The reality will be rather different If we continue to emit ever-greater quantities of CO2 and other greenhouse gases into the atmosphere, then average global temperatures will rise by 2°C over the next three decades compared to pre-industrial times. Most scientists agree that anything higher is dangerous, though many argue that even this is too much. As the battles to reach an agreement in Paris begin, and with so much at stake, it is perhaps curious that few people really understand what a 2°C rise in average temperatures will mean. Rather than thinking about how much nicer it will be to have summers that are 2°C warmer, we should think about the planet more like we think about our bodies. The average temperature of the planet today is around 15°C, one degree more than it was in 1750. Over the next three decades, if we do not stop polluting the atmosphere at an ever increasing rate, ecosystems will move 60 miles towards the poles, and a 100 yards up hillsides. The warming of the world may also change our values.

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