In this newsletter:
1) British Antarctic Snowfall Study Deepens The Mystery Of Global Warming
Outer Place, 9 April 2018
2) Solar Activity Over Last 9000 Years Sheds New Light On Natural Variability
Chi Ju Wu et al. (2018) Astronomy & Astrophysics 5 April 2018
3) Prof Nir Shaviv: The Cosmic Ray Climate Link
GWPF TV, 4 April 2018
4) Wheat In The Heat: New Food Crops Can Withstand Constant 40C Temperatures
Mark Hillsdon, The Guardian, 23 March 2018
5) How Scientists Found And Removed ‘False Warming’ In Satellite Data
University of Alabama, Huntsville, 6 April 2018
6) GWPF Criticises Ofcom For Getting It Wrong On IPCC And Extreme Weather
Global Warming Policy Foundation, 10 April 2018
Full details:
1) British Antarctic Snowfall Study Deepens The Mystery Of Global Warming
Outer Place, 9 April 2018
Over the past century, the Antarctic has gone from being a vast Terra Incognita to a continent-sized ticking time bomb: according to NASA, Antarctica has lost “approximately 125 gigatons of ice per year [between 2002 and 2016], causing global sea level to rise by 0.35 millimeters per year.”
If global temperatures continue to rise, Antarctica’s melting glaciers will cause the oceans to rise, as well as drastic changes in climate. However, new research by British Antarctic Survey shows that Antarctica paradoxically saw a 10 percent increase in snowfall over the last 200 years.
The research comes from 79 ice core samples collected across the continent, and the estimated increase in snow represents about 272 giga tonnes of water.
“There is an urgent need to understand the contribution of Antarctic ice to sea-level rise and we use a number of techniques to determine the balance between snowfall and ice loss,” said lead author on the study, Dr. Liz Thomas.
“When ice loss is not replenished by snowfall then sea level rises…Our new results show a significant change in the surface mass balance [from snowfall] during the 20th century. The largest contribution is from the Antarctic Peninsula, where the annual average snowfall during the first decade of the 21st century is 10 percent higher than at the same period in the 19th century.”
The increase in snowfall doesn’t contradict previous estimates of ice loss around Antarctica’s coast, but it does make the picture more complicated.
Previous climate change models, proposed in 2013, predicted that global sea levels would rise by a meter by the year 2100 due in part to melting Antarctic ice, but those estimates have proven to be flawed.
Dr. Thomas echoes the advice of Tim Naish, who acknowledged that the Antarctic is an important factor in climate change, but still a poorly understood one:
“There is an international effort to create computer simulations of future sea-level rise in a warming world. It is complex and challenging for scientists to fully understand and interpret changes in the ice that we see happening today. We know that the two major influencers affecting change—the mass gain (from snowfall) and the mass loss (from melt)—are acting differently from one another. Our new findings take us a step towards improving our knowledge and understanding.”
Full post
See also:
Outer Place, 9 April 2018
Over the past century, the Antarctic has gone from being a vast Terra Incognita to a continent-sized ticking time bomb: according to NASA, Antarctica has lost “approximately 125 gigatons of ice per year [between 2002 and 2016], causing global sea level to rise by 0.35 millimeters per year.”
If global temperatures continue to rise, Antarctica’s melting glaciers will cause the oceans to rise, as well as drastic changes in climate. However, new research by British Antarctic Survey shows that Antarctica paradoxically saw a 10 percent increase in snowfall over the last 200 years.
The research comes from 79 ice core samples collected across the continent, and the estimated increase in snow represents about 272 giga tonnes of water.
“There is an urgent need to understand the contribution of Antarctic ice to sea-level rise and we use a number of techniques to determine the balance between snowfall and ice loss,” said lead author on the study, Dr. Liz Thomas.
“When ice loss is not replenished by snowfall then sea level rises…Our new results show a significant change in the surface mass balance [from snowfall] during the 20th century. The largest contribution is from the Antarctic Peninsula, where the annual average snowfall during the first decade of the 21st century is 10 percent higher than at the same period in the 19th century.”
The increase in snowfall doesn’t contradict previous estimates of ice loss around Antarctica’s coast, but it does make the picture more complicated.
Previous climate change models, proposed in 2013, predicted that global sea levels would rise by a meter by the year 2100 due in part to melting Antarctic ice, but those estimates have proven to be flawed.
Dr. Thomas echoes the advice of Tim Naish, who acknowledged that the Antarctic is an important factor in climate change, but still a poorly understood one:
“There is an international effort to create computer simulations of future sea-level rise in a warming world. It is complex and challenging for scientists to fully understand and interpret changes in the ice that we see happening today. We know that the two major influencers affecting change—the mass gain (from snowfall) and the mass loss (from melt)—are acting differently from one another. Our new findings take us a step towards improving our knowledge and understanding.”
Full post
See also:
2) Solar Activity Over Last 9000 Years Sheds New Light On Natural Variability
Chi Ju Wu et al. (2018) Astronomy & Astrophysics 5 April 2018
A new consistent reconstruction of the solar activity offers a more reliable estimate of the long-term evolution of the solar variability
Chi Ju Wu et al. (2018) Solar activity over nine millennia: A consistent multi-proxy reconstruction. Astronomy & Astrophysics 5 April 2018
Chi Ju Wu, I. G. Usoskin, N. Krivova, G. A. Kovaltsov, M. Baroni, E. Bard, and S. K. Solanki
Abstract
Aims. The solar activity in the past millennia can only be reconstructed from cosmogenic radionuclide proxy records in terrestrial archives. However, because of the diversity of the proxy archives, it is difficult to build a homogeneous reconstruction. All previous studies were based on individual, sometimes statistically averaged, proxy datasets. Here we aim to provide a new consistent multiproxy reconstruction of the solar activity over the last 9000 years, using all available long-span datasets of 10Be and 14C in terrestrial archives.
Methods. A new method, based on a Bayesian approach, was applied for the first time to solar activity reconstruction. A Monte Carlo search (using the χ2 statistic) for the most probable value of the modulation potential was performed to match data from different datasets for a given time. This provides a straightforward estimate of the related uncertainties. We used six 10Be series of different lengths (from 500–10000 years) from Greenland and Antarctica, and the global 14C production series. The 10Be series were resampled to match wiggles related to the grand minima in the 14C reference dataset. The stability of the long data series was tested.
Results. The Greenland Ice-core Project (GRIP) and the Antarctic EDML (EPICA Dronning Maud Land) 10Be series diverge from each other during the second half of the Holocene, while the 14C series lies in between them. A likely reason for the discrepancy is the insufficiently precise beryllium transport and deposition model for Greenland, which leads to an undercorrection of the GRIP series for the geomagnetic shielding effect. A slow 6–7-millennia variability with lows at ca. 5500 BC and 1500 AD in the longterm evolution of solar activity is found. Two components of solar activity can be statistically distinguished: the main component, corresponding to the ‘normal’ moderate level, and a component corresponding to grand minima. A possible existence of a component representing grand maxima is indicated, but it cannot be separated from the main component in a statistically significant manner.
Conclusions. A new consistent reconstruction of solar activity over the last nine millennia is presented with the most probable values of decadal sunspot numbers and their realistic uncertainties. Independent components of solar activity corresponding to the main moderate activity and the grand-minimum state are identified; they may be related to different operation modes of the dynamo. […]
Full paper
3) Prof Nir Shaviv: The Cosmic Ray Climate Link
GWPF TV, 4 April 2018
Presentation by Professor Nir Shaviv on the The Cosmic Ray Climate Link: From Geological Timescales to 20th Century Climate Change. London, 4 April 2018
Click on image above to watch presentation
4) Wheat In The Heat: New Food Crops Can Withstand Constant 40c Temperatures
Mark Hillsdon, The Guardian, 23 March 2018
Durum wheat varieties can withstand 40C heat along the Senegal River basin, and could produce 600,000 tonnes of food
After four years of trials, scientists have found a wheat variety that can grow quickly and survive in sub-Saharan heat. Photograph: Filippo Bassi/Icarda
In the northern Senegalese village of Ndiayene Pendao, close to the border with Mauritania, Fatouma Sow is pulling weeds. Her team of female farmers tread carefully among the tall, ripening plants as they prepare to harvest the country’s first ever crop of durum wheat.
They had grown onions and tomatoes on the one-hectare plot (2.47 acres), Sow explains, but the crops took too long to grow and disrupted the essential rice growing season. Now the wheat offers a fast-growing, lucrative alternative.
Following four years of trials, which saw thousands of wheat varieties tested in the unforgiving sub-Saharan heat, scientists have successfully turned what was first thought of as a “crazy idea” into a vital new food crop. With more than 1 million smallholders living along the Senegal River basin, which also runs through Mali and Mauritania, it was an important strategic area to trial the wheat.
The strain of wheat can withstand constant 40C [104 degrees Fahrenheit] temperatures, and has been developed by the International Centre for Research in the Dry Areas (Icarda). The so-called drylands cover more than 40% of the world’s land surface and despite the challenges, remain huge centres of agriculture, supporting half the world’s livestock.
Full story
5) How Scientists Found And Removed ‘False Warming’ In Satellite Data
University of Alabama, Huntsville, 6 April 2018
Scientists in the Earth System Science Center (ESSC) at The University of Alabama in Huntsville (UAH) have calculated how much false warming NOAA-14 reported so the false warming could be removed from a long-term global atmospheric temperature record collected by MSU’s on satellites since mid-November 1978.
Weather Satellite Wanders Through Time, Space, Causing Stray Warming to Contaminate Data
In the late 1990s, the NOAA-14 weather satellite went wandering through time and space, apparently changing the record of Earth’s climate as it went.
Designed for an orbit synchronized with the sun, NOAA-14’s orbit from pole to pole was supposed to cross the equator at 1:30 p.m. on the sunlit side of the globe and at 1:30 a.m. on the dark side, 14 times each day. One of the instruments it carried was a microwave sounding unit (MSU), which looked down at the world and collected data on temperatures in Earth’s atmosphere and how those temperatures changed through time.
By the time NOAA-14 was finishing its useful life in 2005, however, it had strayed eastward from its intended orbit until it was crossing the equator not at 1:30 but at about 8:00. That pushed its early afternoon passage until after dark and its middle of the night measurements until well after dawn.
Because local temperatures typically change between 1:30 and 8:00, this introduced spurious temperature changes that had to be calculated and removed from long-term temperature datasets that use data from satellite instruments.
The drift also changed the satellite’s orientation relative to the sun, so that instead of instruments being shielded from sunlight in a consistent way, the sun’s rays peaked into unshielded and open crevices and other places where intense sunlight could influence the sensors. It warmed the MSU, which caused it to look at the atmosphere’s mid-troposphere (from the surface up to about 40,000 feet) as very slightly warmer than it actually was relative to its initial 1:30 crossing time.
Using data from weather satellites that stayed closer to home than NOAA-14, scientists in the Earth System Science Center (ESSC) at The University of Alabama in Huntsville (UAH) have calculated how much false warming NOAA-14 reported so the false warming could be removed from a long-term global atmospheric temperature record collected by MSU’s on satellites since mid-November 1978.
Details of that research have been published in the International Journal of Remote Sensing, and are available online at: https://www.tandfonline.com/doi/full/10.1080/01431161.2018.1444293
The wandering satellite became an issue when Dr. John Christy, director of UAH’s ESSC and lead author of the study, and Dr. Roy Spencer, an ESSC principal research scientist, were updating and revising UAH’s satellite-based global temperature dataset. (Version 6.0 was completed in 2016.) While they knew NOAA-14 had strayed from its path, a closer look showed the warming reported by the MSU on NOAA-14 was out of kilter with temperature data collected by instruments on other NOAA satellites. This seemed to be especially true in the tropical mid-troposphere.
Full post
6) GWPF Criticises Ofcom For Getting It Wrong On IPCC And Extreme Weather
Global Warming Policy Foundation, 10 April 2018
London, 10 April: The Global Warming Policy Foundation (GWPF) has criticised Ofcom for its ruling against a BBC interview with Lord Lawson.
In his interview with the BBC’s Today Programme on 10 August 2017, Lord Lawson pointed out that while some extreme events had increased, others had diminished.
Overall, however, extreme weather events had not increased according to the IPCC:
“For example, for example he [Al Gore] said that there has been a growing, increase which is continuing, in extreme weather events. There hasn’t been. All the experts say there hasn’t been. The IPCC, the Inter-Governmental Panel on Climate Change, which is the sort of voice of the consensus, concedes that there has been no increase in extreme weather events. Extreme weather events have always happened. They come and go. And some kinds of extreme weather events, there’s a particular time increase, whereas others, like tropical storms, diminish”.
Lord Lawson’s statement was based on the IPCC’s key findings in its 2013 5th Assessment Report (see summary of IPCC conclusions at ttp://rogerpielkejr.blogspot.co.uk/2013/10/coverage-of-extreme-events-in-ipcc-ar5.html)
“Overall, the most robust global changes in climate extremes are seen in measures of daily temperature, including to some extent, heat waves. Precipitation extremes also appear to be increasing, but there is large spatial variability”
“There is limited evidence of changes in extremes associated with other climate variables since the mid-20th century”
“Current datasets indicate no significant observed trends in global tropical cyclone frequency over the past century … No robust trends in annual numbers of tropical storms, hurricanes and major hurricanes counts have been identified over the past 100 years in the North Atlantic basin”
“In summary, there continues to be a lack of evidence and thus low confidence regarding the sign of trend in the magnitude and/or frequency of floods on a global scale”
“In summary, there is low confidence in observed trends in small-scale severe weather phenomena such as hail and thunderstorms because of historical data inhomogeneities and inadequacies in monitoring systems”
“In summary, the current assessment concludes that there is not enough evidence at present to suggest more than low confidence in a global-scale observed trend in drought or dryness (lack of rainfall) since the middle of the 20th century due to lack of direct observations, geographical inconsistencies in the trends, and dependencies of inferred trends on the index choice. Based on updated studies, AR4 conclusions regarding global increasing trends in drought since the 1970s were probably overstated. However, it is likely that the frequency and intensity of drought has increased in the Mediterranean and West Africa and decreased in central North America and north-west Australia since 1950”
“In summary, confidence in large scale changes in the intensity of extreme extratropical cyclones since 1900 is low”
Without providing any evidence to justify disputing the IPCC’s conclusions, Ofcom claimed that Lawson’s statement about extreme weather was incorrect and not sufficiently challenged by the BBC presenter during the interview.
Ofcom, however, appear to base its ruling on information from unnamed complainants, the BBC (and possibly from other unnamed sources) without publishing that information or where it obtained it from. As a result, nobody is able to see it and judge its credibility. It did not ask Lord Lawson for any information regarding his statements.
That Ofcom should judge on scientific matters without justifying their decision sets a worrying precedent concerning the oversight of journalists.
Presenters are not experts and cannot be expected to be. For them to provide a detailed examination of competing viewpoints would be a burden on them and a limitation of the freedom of broadcasters and the BBC, and severely inhibit live discussions, as well as investigative journalism.
The London-based Global Warming Policy Forum is a world leading think tank on global warming policy issues. The GWPF newsletter is prepared by Director Dr Benny Peiser - for more information, please visit the website at www.thegwpf.com.
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