Posted on March 25, 2015 by Bob Berwyn
Influx of cold, fresher water could tip climate scale
FRISCO — Earth scientists have long speculated that a massive infusion of cold and relatively fresh water into the North Atlantic could disrupt a key climate-regulating ocean current, with huge consequences for adjacent land areas.
New measurements of ocean temperatures in the region, along with other climate data, now suggest that the Atlantic Overturning Current has already slowed quite a bit in the past 100 years, and especially since 1970. The current, which is related to the Gulf Stream, helps moderate temperatures in northwestern Europe and northeastern North America.
Further weakening of the current could impact marine ecosystems and sea level as well as weather systems in the US and Europe, scientists say in a new study to be published in Nature Climate Change. Continue reading
Filed under: climate and weather, climate change, global warming, Greenland | Tagged: Atlantic overturning current, global warming, greenland, Gulf Stream | Leave a comment »
Posted on August 23, 2014 by Bob Berwyn
The Fram Strait is a key link in the global ocean circulation system, as the passage for most of the Arctic sea ice exiting the region.
Detailed ocean sediment layers paint clear picture of link between Arctic sea ice movement and ocean currents
FRISCO — An extraordinarily clear deposit of layered seafloor sediments has helped researchers explain the connection between Arctic sea ice movement and the movement of key ocean currents that redistribute warm water across the northern hemisphere.
Specifically, the new study by scientists with the Alfred Wegener Institute in Germany looked at the movement of sea ice through the Fram Strait, between Greenland Svalbard, finding that, when massive quantities of Arctic ice melt and move south through the strait, the Gulf Stream slows, cooling the climate in Europe. Continue reading
Filed under: Arctic, climate and weather, global warming | Tagged: Arctic sea ice, climate change, Fram Strait, Gulf Stream | Leave a comment »
Posted on March 10, 2014 by Bob Berwyn
A composite image assembled from NASA satellite images shows the UK covered with snow during a spell of cold winter weather in January 2010.
Yes, but effects are small compared to changes driven by greenhouse gases
By Summit Voice
FRISCO — After carefully studying cycles of solar activities and matching them against seafloor sediments that offer clues about ocean temperatures, Cardiff University scientists say low sunspot activity may be linked with phases of cold weather in Europe.
The study found that changes in the Sun’s activity can have a considerable impact on the ocean-atmospheric dynamics in the North Atlantic, with potential effects on regional climate.
While the effects of variations in solar energy are small compared to the impacts of increasing greenhouse gas concentrations, the effects of solar output on the ocean and atmosphere should be taken into account when making future climate projections, the researchers said. Continue reading
Filed under: climate and weather, global warming | Tagged: climate, Europe, global warming, Gulf Stream, solar activity | Leave a comment »
Posted on October 10, 2013 by Bob Berwyn
Researchers eye global warming impacts to North Atlantic region
Ocean currents help shape global climate, and understanding how global warming may change those currents will inform more accurate climate projections.
By Summit Voice
FRISCO — Some of the biggest potential global warming impacts could occur if major ocean currents change in strength or direction — a shift in the Gulf Stream, for example, would have major implications for parts of northwestern Europe, kept temperate by the transport of subtropical water.
Some research has suggested that increasing amounts of cold, fresh water in the North Atlantic could have a big impact on the Gulf Stream and other important currents, but there’s not a lot of detailed historic or baseline data against which to measure changes. But that could change in the next few years, as science agencies in the U.S. and the U.K. team up on a $70 million project to study North Atlantic currents. Continue reading
Filed under: climate and weather, Environment, global warming, Greenland | Tagged: climate change, global warming, Gulf Stream, National Oceanography Centre, ocean currents, Thermohaline circulation | Leave a comment »
Posted on January 18, 2013 by Bob Berwyn
‘The ocean is rising and it’s going to keep rising for quite some time’
A NOAA aerial photo shows damage caused by superstorm Sandy along the New Jersey shoreline. Click on the photo to see before and after images on the NASA EO website.
By Bob Berwyn
FRISCO — What until recently was a mostly academic discussion about sea level rise is starting to hit home — literally —as Americans watch devastating storms like Katrina, Irene and Sandy engulf cities and fundamentally alter the shape of coastal areas.
“What is very clear is, the ocean is rising and it’s going to keep rising for quite some time. The difference from last time is, now, there are a lot of people living on the coast,” said Margaret Davidson, acting director of NOAA’s Office of Ocean and Coastal Resource Management. Davidson’s powerpoint presentation is online here, and a video of her presentation should also be posted at the same place soon.
The consequences of rising sea level are likely to be enormous, given that the majority of the country’s population lives along coastlines, and those coastal cities generate a huge percentage of the country’s economic wealth.
“How do we begin to think about that? We’ve never had to think about relocating large populations,” Davidson said, addressing an audience of broadcast meteorologists and climate scientists during the annual Glen Gerberg Weather and Climate Summit in Breckenridge. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: climate change, East Coast, global warming, greenland, Greenland ice sheet, Gulf Stream, King Tide, Margaret Davidson, Netherlands, Sandy, sea level rise | 1 Comment »
Posted on October 18, 2012 by Bob Berwyn
Location of tide stations on the Atlantic coast of North America. Sea-level data for U.S. tide stations are collected and distributed by NOAA’s National Ocean Service.
Rate of increase is highest along the northeast coast
By Summit Voice
SUMMIT COUNTY — Calculating sea level rise has been vexing for climate and ocean scientists. Melting ice and thermal expansion both contribute, but the water doesn’t just go up evenly like a bathtub that’s filling up.
Pinpointing the rate and location of sea level rise is critical for planners tasked with adapting their communities to coastal flooding, said John Boon, emeritus professsor at the Virginia Institute of Marine Science.
“Localized projections of sea-level rise are needed to guide the regional planning and adaptation measures that are being pursued with increasing urgency in many coastal localities,” said Boon, who recently completed a new study showing that the rate of sea level rise is increasing at tidal stations along the Atlantic coast of North America, including those in Norfolk, Baltimore, New York, and Boston. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: Atlantic Ocean, climate, Environment, global warming, Gulf Stream, northeastern United States, sea level rise, Virginia Institute of Marine Science | 2 Comments »
Posted on October 2, 2012 by Bob Berwyn
Is Svalbard ground zero for global warming?
August 2012 global temperatures anomalies.
Svalbard might be ground zero for global warming, with some research suggesting it may warm faster than any other spot on Earth. Photo courtesy, NASA.
By Summit Voice
SUMMIT COUNTY — A group of researchers led by a Columbia University climate scientist William D’Andrea took direct aim at misleading information about historic climate records this week, releasing a study showing that temperatures in some parts of the Arctic are higher than they’ve been at any time during the past 1,800 years.Global warming deniers have used evidence of warmer temperatures during the so-called Medieval Warm Period to undermine the reality that heat-trapping greenhouse gases are inexorably warming the planet.
But the climate reconstruction from Svalbard casts new doubt on the reach of the Medieval Warm Period, and undercuts skeptics who argue that current warming is also natural. Since 1987, summers on Svalbard have been 2 degrees to 2.5 degrees Celsius (3.6 to 4.5 degrees fahrenheit) hotter than they were there during warmest parts of the Medieval Warm Period, according to the new study. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: Arctic, climate change, global warming, Gulf Stream, Keck Geology Consortium, Medieval Warm Period, Svalbard, West Spitsbergen Current | Leave a comment »