New paper finds the world’s most commonly used climate model produces predictions ‘not realistic’ — Published in the Journal of Climate
New paper finds the world’s most commonly used climate model produces predictions “not realistic”
A paper published today in the Journal of Climate finds that the world’s most commonly used climate model [CCSM3] is unable to reproduce the observed sea surface temperature changes influencing two of the most important natural oscillations, the North Atlantic Oscillation [NAO] and Atlantic meridional overturning circulation [AMOC], which in turn influence global climate change. The authors conclude, “Hence, although there is some potential climate predictability in CCSM3, it is not realistic.”
Note: CCSM3, and it’s even worse successor CCSM5, are the most commonly used climate models of the IPCC. GIGO
Journal of Climate 2013 ; e-View
The influence of the AMOC variability on the atmosphere in CCSM3
Claude Frankignoul and Guillaume Gastineau
LOCEAN, University Pierre and Marie Curie, Paris, France
Woods Hole Oceanographic Institution, USA
The influence of the Atlantic meridional overturning circulation (AMOC) variability on the atmospheric circulation is investigated in a control simulation of the NCAR Community Climate System Model 3, where the AMOC evolves from an oscillatory regime into a red-noise regime. In the latter, an AMOC intensification is followed during winter by a positive NAO. The atmospheric response is robust and controlled by AMOC-driven SST anomalies, which shift the heat release to the atmosphere northward near the Gulf Stream/North Atlantic Current. This alters the low-level atmospheric baroclinicity and shifts the maximum eddy growth northward, affecting the storm track and favoring a positive NAO. The AMOC influence is detected in the relation between seasonal upper ocean heat content or SST anomalies and winter sea level pressure. In the oscillatory regime, no direct AMOC influence is detected in winter. However, an upper ocean heat content anomaly resembling the AMOC footprint precedes a negative NAO. This opposite NAO polarity seems due to the southward shift of the Gulf Stream during AMOC intensification, displacing the maximum baroclinicity southward near the jet exit. As the mode has somewhat different patterns when using SST, the wintertime impact of the AMOC lacks robustness in this regime. However, none of the [climate model] signals compares well with the observed influence of North Atlantic SST [Sea Surface Temperature] anomalies on the NAO because SST is dominated in CCSM3 by the meridional shifts of the Gulf Stream/North Atlantic Current that co-vary with the AMOC. Hence, although there is some potential climate predictability in CCSM3, it is not …
Looming Weak Solar Activity May Herald Frosty Times: ‘Current solar cycle, possibly the weakest in 100 years, is approaching its maximum. This may signal a future low period for the sun, probably not unlike the one that caused the Little Ice Age from mid-16th to mid-19th centuries’
Looming Weak Solar Activity May Herald Frosty Times
The current solar activity cycle, possibly the weakest in 100 years, is approaching its maximum. This may signal a future low period for the sun, probably not unlike the one that caused the so-called Little Ice Age from the mid-16th to mid-19th centuries.
The sun is currently at the maximum of Solar Cycle 24, but as this graph shows, there are far fewer sunspots during this peak than there have been in past cycles (Image credit: Hathaway/NASA/MSFC)
Solar activity can be easily monitored by the number of sun spots. Regular recordings of the phenomenon have been available since the middle of the 18th century, with the star’s activity reaching peaks about every 11 years. The current Solar Cycle 24, is about to pass its prime in a matter of months, according to observations.
One indicator of the upcoming change is the reduction of solar magnetic activity. Every cycle peak the sun’s magnetic field flips polarity due to reorganization of its inner dynamo.
“The sun’s north pole has already changed sign, while the south pole is racing to catch up,” says Phil Scherrer, solar physicist at Stanford’s Wilcox Solar Observatory, which has been monitoring the sun’s polar magnetic fields since 1976.
“Soon, however, both poles will be reversed, and the second half of Solar Max will be underway,” he added as cited by NASA Science.
Solar Cycle 24 is unusual on several accounts. It came late about a year, with extremely low activity recorded throughout 2009, which made astronomers shift a predicted 2012 peak to 2013. Also a few years ago the northern hemisphere of the sun became significantly more active than the southern, with the latter trying to catch up.
Further muddying the water is the fact that the previous four cycles had double peaks rather than single ones. The sun was quite active in 2011, but then went into a lull, with fewer-than-expected sunspots and solar flares in 2012 and 2013.
The current cycle is likely to have an in-between peak too, some NASA scientists say, with a second spike expected in late 2013 to early 2014. The increased activity would be due to the lagging southern hemisphere as the main driver.
Possible explanations for the sun’s latest odd behavior were discussed last month at a meeting of the Astronomical Society’s Solar Physics Division. Scientists agree that Cycle 24 is …
New paper finds sea levels rose naturally to 29 feet higher than the present during last interglacial — Published in Nature Geoscience
New paper finds sea levels rose naturally to 29 feet higher than the present during last interglacial
A new paper published in Nature Geoscience finds “sea level rose to about 9 meters [29.5 feet] above the present at the end of the last interglacial.” The authors observe fossil coral reefs in Western Australia located 9.5 meters [31 feet] above the present sea level. Prior research has demonstrated Greenland temperatures were 8C higher than the present during the last interglacial. Obviously, this dramatic climate change was entirely driven by natural variability while CO2 remained “safe.” By comparison, the warming periods of the current interglacial, including the current warm period, are entirely within natural variability, not unprecedented, and not unusual. Furthermore, there is no evidence of a runaway greenhouse effect or runaway positive-feedbacks despite a climate that was naturally much warmer during the last interglacial.
Top two lines show sea levels during the last interglacial were about 9 meters higher than the present [bottom 4 lines]
Ice sheet collapse following a prolonged period of stable sea level during the last interglacial
Michael J. O’Leary, Paul J. Hearty, William G. Thompson, Maureen E. Raymo, Jerry X. Mitrovica & Jody M. Webster
Nature Geoscience (2013) doi:10.1038/ngeo1890
Published online 28 July 2013Abstract: During the last interglacial period, 127–116 kyr ago, global mean sea level reached a peak of 5–9 m above present-day sea level. However, the exact timing and magnitude of ice sheet collapse that contributed to the sea-level highstand is unclear. Here we explore this timing using stratigraphic and geomorphic mapping and uranium-series geochronology of fossil coral reefs and geophysical modelling of sea-level records from Western Australia. We show that between 127 and 119 kyr ago, eustatic sea level remained relatively stable at about 3–4 m above present sea level. However, stratigraphically younger fossil corals with U-series ages of 118.1±1.4 kyr are observed at elevations of up to 9.5 m above present mean sea level. Accounting for glacial isostatic adjustment and localized tectonics, we conclude that eustatic sea level rose to about 9 m above present at the end of the last interglacial. We suggest that in the last few thousand years of the interglacial, a critical ice sheet stability threshold was crossed, resulting in the catastrophic collapse of polar ice sheets and substantial sea-level rise.…
Keystone XL Pipeline: “No Material Impact” on U.S. Carbon Dioxide Emissions
Paul C. “Chip” Knappenberger
President Obama has a ticklish situation on his hands with the Keystone XL pipeline—one long on symbolism but short on practical impacts.
He took a few minutes out of his June 25th speech unveiling his Climate Action Plan to specifically address the pipeline issue:
Now, I know there’s been, for example, a lot of controversy surrounding the proposal to build a pipeline, the Keystone pipeline, that would carry oil from Canadian tar sands down to refineries in the Gulf. And the State Department is going through the final stages of evaluating the proposal. That’s how it’s always been done. But I do want to be clear: Allowing the Keystone pipeline to be built requires a finding that doing so would be in our nation’s interest. And our national interest will be served only if this project does not significantly exacerbate the problem of carbon pollution. The net effects of the pipeline’s impact on our climate will be absolutely critical to determining whether this project is allowed to go forward. It’s relevant.
The president is balancing “our national interest” in the pipeline—which surely includes factors (or, at least, the perception of factors) like growing the economy, adding jobs, and increasing our energy security—with the pipeline’s (perceived) impacts on the climate via the carbon dioxide emissions (which he oddly terms “carbon pollution”) associated with the oil it will carry.
When it comes to growing the economy, adding jobs, and/or increasing our energy security, the estimates of the impact of the Keystone XL pipeline are all over the place—but all positive. The more level-headed analyses generally indicate the gains will probably be rather small in the overall sense.
When it comes to affecting the climate, again, the estimates are all over the place, and largely depend on assumptions as to how much leverage the Keystone XL pipeline will have on opening up the Canadian tar sands to further development. Folks who claim that the pipeline’s approval would mean “game over” for the climate assume that the pipeline is the key to opening up the 1.7+ trillion barrels of oil that are estimated to be contained in the Canadian tar sands formation. More sober analyses argue that market demands are such that the oil will be brought to market with or without the Keystone XL pipeline and, as …
New paper finds existing cropland could feed an additional 4 billion people if not wasted on biofuels
New paper finds existing cropland could feed an additional 4 billion people if not wasted on biofuels
Paging Paul Ehrlich:Existing cropland could feed four billion moreby Staff WritersMinneapolis MN (SPX) Aug 08, 2013
Demand for crops is expected to double by 2050 as population grows and increasing affluence boosts meat consumption.
The world’s croplands could feed 4 billion more people than they do now just by shifting from producing animal feed and biofuels to producing exclusively food for human consumption, according to new research from the Institute on the Environment at the University of Minnesota.
Even a smaller, partial shift from crop-intensive livestock such as feedlot beef to food animals such as chicken or pork could increase agricultural efficiency and provide food for millions, the study says.
“We essentially have uncovered an astoundingly abundant supply of food for a hungry world, hidden in plain sight in the farmlands we already
cultivate,” says graduate research assistant Emily Cassidy, lead author of the paper published in Environmental Research Letters. “Depending on the extent to which farmers and consumers are willing to change current practices, existing croplands could feed millions or even billions more people.”
Demand for crops is expected to double by 2050 as population grows and increasing affluence boosts meat consumption. Meat takes a particularly big toll on food security because it takes up to 30 crop calories to produce a single calorie of meat.
In addition, crops are increasingly being used for biofuels [which don’t even reduce emissions] rather than food production. This study sought to quantify the benefit to food security that would accrue if some or all of the lands used to produce animal feed and fuel were reallocated to directly produce food for people.
To get at that question, Cassidy and colleagues first mapped the extent and productivity of 41 major crops between 1997 and 2003, adjusting numbers for imports and exports and calculating conversion efficiencies of animal feed using U.S. Department of Agriculture data.
The researchers assumed humans need an average of 2,700 calories per day, and grazing lands and animals were not included in the study. Among the team’s findings:
+ Only 12 percent of crop calories used for animal feed end up as calories consumed by humans.
+ Only 55 percent of crop calories worldwide directly nourish people.
+ Growing food exclusively for direct human consumption could boost available food calories up to …
400 PPM CO2 Update! ‘Coldest summer on record at North Pole — Highest Aug. Arctic ice extent since 2006 — Record high Aug. Antarctic ice extent — No major hurricane strikes for 8 years — Slowest tornado season on record — No global warming for 17 years – 2nd slowest fire season on record’
- Coldest summer on record at the North Pole
- Highest August Arctic ice extent since 2006
- Record high August Antarctic ice extent
- No major hurricane strikes (Cat 3 or larger) for eight years
- Slowest tornado season on record
- No global warming for 17 years
- Second slowest fire season on record
- Four of the five snowiest northern hemisphere winters have occurred since 2008
New paper predicts solar activity will decline over 21st century to average Holocene levels – Published in Climate of the Past
New paper predicts solar activity will decline over 21st century to average Holocene levels
A paper published today in Climate of the Past reconstructs solar activity over the Holocene [past 10,000 years] and finds solar activity during the 20th century was at relatively high levels in comparison to the rest of the Holocene, but that “Solar activity is during 28% of the time higher than the modern average (650 MeV), but the absolute values remain weakly constrained due to uncertainties in the normalisation of the solar modulation to instrumental data.” The authors predict solar activity will decrease in the 21st century, stating, “Autoregressive modelling suggests a declining trend of solar activity in the 21st century towards average Holocene conditions.”
Reconstructed Total Solar Irradiance [TSI] over the Holocene
Future solar activity is predicted to decline to “average Holocene conditions”
Clim. Past, 9, 1879-1909, 2013www.clim-past.net/9/1879/2013/doi:10.5194/cp-9-1879-2013
A reconstruction of radiocarbon production and total solar irradiance from the Holocene 14C and CO2 records: implications of data and model uncertaintiesR. Roth and F. JoosClimate and Environmental Physics, Physics Institute, University of Bern, Bern, SwitzerlandOeschger Centre for Climate Change Research, University of Bern, Bern, SwitzerlandAbstract. Radiocarbon production, solar activity, total solar irradiance (TSI) and solar-induced climate change are reconstructed for the Holocene (10 to 0 kyr BP), and TSI is predicted for the next centuries. The IntCal09/SHCal04 radiocarbon and ice core CO2 records, reconstructions of the geomagnetic dipole, and instrumental data of solar activity are applied in the Bern3D-LPJ, a fully featured Earth system model of intermediate complexity including a 3-D dynamic ocean, ocean sediments, and a dynamic vegetation model, and in formulations linking radiocarbon production, the solar modulation potential, and TSI. Uncertainties are assessed using Monte Carlo simulations and bounding scenarios. Transient climate simulations span the past 21 thousand years, thereby considering the time lags and uncertainties associated with the last glacial termination.Our carbon-cycle-based modern estimate of radiocarbon production of 1.7 atoms cm−2 s−1 is lower than previously reported for the cosmogenic nuclide production model by Masarik and Beer (2009) and is more in-line with Kovaltsov et al. (2012). In contrast to earlier studies, periods of high solar activity were quite common not only in recent millennia, but throughout the Holocene. Notable deviations compared to earlier reconstructions are also found on decadal to centennial timescales. We show that earlier Holocene reconstructions, not accounting for the interhemispheric gradients in radiocarbon, are biased low. Solar activity …