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A study based on 1,000 years of temperature records suggests global warming is not progressing as fast as it would under the most severe emissions scenarios outlined by the Intergovernmental Panel on Climate Change. Natural decade-to-decade variability in surface temperatures can account for some much-discussed recent changes in the rate of warming. Empirical data, rather than climate models, were used to estimate this variability.

Scientists have presented the geophysical impact of phytoplankton that triggers positive feedback in the Arctic warming when the warming-induced melting of sea ice stimulates phytoplankton growth.

Darkening of the Greenland Ice Sheet is projected to continue as a consequence of continued climate warming, according to experts.

Climate models calculate a changing mix of clouds and emissions that interact with solar energy. To narrow the broad range of possible answers from a climate model, researchers analyzed the effect of several proven numerical stand-ins for atmospheric processes on the energy flux at the top of the atmosphere. They found that the flux is the main driver of surface temperature change.

Through a combination of data analysis and numerical modeling work, researchers have found a record of the ancient moon-forming giant impact observable in stony meteorites. The research indicates numerous kilometer-sized fragments from the giant impact struck main belt asteroids at much higher velocities than typical main belt collisions, heating the surface and leaving behind a permanent record of the impact event.

A key question in the climate debate is how the occurrence and distribution of species is affected by climate change. But without information about natural variation in species abundance it is hard to answer. In a major study, researchers can now for the first time give us a detailed picture of natural variation.

Armadas of icebergs were probably not the cause of abrupt episodes of cooling in the North Atlantic over the past 440,000 years, according to new research.

Global climate has undergone periods of stability, but also instability, with abrupt, rapid and substantial climate changes occurring as a consequence of natural processes scientists still don't understand. A paleoceanographer has contributed to the field in a recent paper, which demonstrates the influence of rapid climate change on marine ecosystems near Venezuela tens of thousands of years ago and shows how changes there were accompanied by simultaneous changes globally.

Early schemes to model the Greenland and Antarctic ice sheets and their impact on sea levels failed to accurately account for changes caused by snowfall and snow melt. These changes depend on ice sheet elevation and region. Researchers developed a new method that includes the effects of elevation and region.

Many scientists have studied fossils from gigantic marine lizards called mosasaurs that lived at the time of the dinosaurs and flourished in ancient seas, but little is known about aspects of their breeding and birth. Investigators have gained new insights from young mosasaur specimens collected over 100 years ago that had previously been thought to belong to ancient marine birds. The team noted that the specimens show a variety of features related to the jaws and teeth that are only found in mosasaurs.

New evidence by geologists dates the closure of an ancient seaway at 13 to 15 million years ago and challenges accepted theories about the rise of the Isthmus of Panama and its impact on world climate and animal migrations.

The onset of northern hemispheric glaciation cycles three million years ago has dramatically changed Arctic climate. Scientists have now for the first time reconstructed the history of Arctic climate based on records archived in ferromanganese crusts.

The polar bear, one of the largest carnivorous mammals on Earth, is being made vulnerable by the series of dangers it faces. An international team has established a guide to evaluate the condition of its health and although the polar bear's biggest threat is climate change, plastic pollution and environmental contaminants in its habitat are starting to affect its endocrine system and reproduction. Climate change is undoubtedly the main threat to polar bears. They also suffer from nutritional stress, reduction of polar ice, human contact and diseases and parasites. But that's not all, researchers warn.

Seventy percent of glacier ice in British Columbia and Alberta could disappear by the end of the 21st century, creating major problems for local ecosystems, power supplies, and water quality, according to a new study.

Polar bears, increasingly forced on shore due to sea ice loss, may be eating terrestrial foods including berries, birds and eggs, but any nutritional gains are limited to a few individuals and likely cannot compensate for lost opportunities to consume their traditional, lipid-rich prey -- ice seals.

The volcanologist Stephen Self, an expert on super-eruptions, was the first modern-day scientist to visit Tambora in Indonesia, the site of the largest volcanic eruption in 1,000 years. On the 200th anniversary of its eruption in 1815, Self and others warn of the ever-present dangers of volcanoes like Tambora. Globally dispersed clouds of sulfate aerosols could lead to cooling, crop failures and famine, as happened in the 'year without a summer' of 1816.

A new study reports that marine ecosystems can take thousands, rather than hundreds, of years to recover from climate-related upheavals. The study's authors analyzed thousands of invertebrate fossils to show that ecosystem recovery from climate change and seawater deoxygenation might take place on a millennial scale.

A new study has confirmed the existence of a positive feedback operating in climate change whereby warming itself may amplify a rise in greenhouse gases resulting in additional warming.

Cores of marine sediment reveal an earthquake history of the Cinarcik Segment, a main branch of NAF, and suggest a seismic gap where the next earthquake is likely to rupture, as detailed in a new study.

New research into the changing ecology of thousands of shallow lakes on the North Slope of Alaska suggests that in scenarios of increasing global temperatures, methane-generating microbes, found in thawing lake sediments, may ramp up production of the potent greenhouse gas -- which has a global warming potential 25 times greater than carbon dioxide.