Showing posts with label sunspots. Show all posts
Showing posts with label sunspots. Show all posts

Thursday, September 24, 2009

Solar Winds are Blowing

This story has been sitting in my inbox for some time, but here is an excellent report that describes it all well.

A scientific assumption that has survived for perhaps a couple of centuries has just been shown false. That is how important this item is. We now need to properly map the solar wind for the next few decades to determine what correlations exist if any at all. And we also need to stamp all published research on sunspots and solar energy as pre 2009.

It is also exciting. We have discovered a significant variable that was assumed fairly stable or at least tied to an eleven year cycle to now be highly variable over much shorter time ranges. It may be actually linked directly to global weather effects.

Of course we will need to monitor the variation closely for a long time before we know anything but it is today a surprise to science and will cause all the text books to be rewritten even now.

Press Release 09-171

More to Solar Cycle Than Sunspots
Sun also bombards Earth with high-speed streams of wind

September 17, 2009

Challenging conventional wisdom, new research finds that the number of sunspots provides an incomplete measure of changes in the sun's impact on Earth over the course of the 11-year solar cycle. The study, led by scientists at the National Center for Atmospheric Research (NCAR) and the University of Michigan, finds that Earth was bombarded last year with high levels of solar energy at a time when the sun was in an unusually quiet phase and sunspots had virtually disappeared.

"The sun continues to surprise us," says lead author Sarah Gibson of NCAR's High Altitude Observatory. "The solar wind can hit Earth like a fire hose even when there are virtually no sunspots."

The study, also written by scientists at NOAA and NASA, is being published today in the Journal of Geophysical Research. It was funded by NASA and by the National Science Foundation, NCAR's sponsor.

"It is vitally important to realize that the 'quiet' sun really isn't all that quiet," says Rich Behnke, program director in NSF's Division of Atmospheric Sciences. "These high-speed streams of wind can affect many of our communications and navigation systems. And they can come at any time, during any part of the solar cycle."

Scientists for centuries have used sunspots, which are areas of concentrated magnetic fields that appear as dark patches on the solar surface, to determine the approximately 11-year solar cycle. At solar maximum, the number of sunspots peaks. During this time, intense solar flares occur daily and geomagnetic storms frequently buffet Earth, knocking out satellites and disrupting communications networks.
Gibson and her colleagues focused instead on another process by which the sun discharges energy. The team analyzed high-speed streams within the solar wind that carry turbulent magnetic fields out into the solar system.

When those streams blow by Earth, they intensify the energy of the planet's outer radiation belt. This can create serious hazards for Earth-orbiting satellites and affect global communications systems, while also threatening astronauts in the International Space Station. Auroral storms light up the night sky repeatedly at high latitudes as the streams move past, driving mega-ampere electrical currents a few hundred miles above Earth's surface. All that energy heats and expands the upper atmosphere. This expansion pushes denser air higher, slowing down satellites and causing them to drop to lower altitudes.

Scientists previously thought that the streams largely disappeared as the solar cycle reached minimum. But when the study team compared measurements within the current solar minimum interval, taken in 2008, with measurements of the last solar minimum in 1996, they found that the Earth in 2008 was continuing to resonate with the effects of the streams. Although the current solar minimum has fewer sunspots than any minimum in 75 years, the sun's effect on Earth's outer radiation belt, as measured by electron fluxes, was more than three times greater last year than in 1996.

Gibson said that observations this year show that the winds have finally slowed, almost two years after sunspots reached the levels of last cycle's minimum.

The authors note that more research is needed to understand the impacts of these high-speed streams on the planet. The study raises questions about how the streams might have affected Earth in the past when the sun went through extended periods of low sunspot activity, such as a period known as the Maunder minimum that lasted from about 1645 to 1715.

"The fact that Earth can continue to ring with solar energy has implications for satellites and sensitive technological systems," Gibson says. "This will keep scientists busy bringing all the pieces together."

Buffeting Earth with streams of energy

For the new study, the scientists analyzed information gathered from an array of space- and ground-based instruments during two international scientific projects: the Whole sun Month in the late summer of 1996 and the Whole Heliosphere Interval in the early spring of 2008. The solar cycle was at a minimal stage during both the study periods, with few sunspots in 1996 and even fewer in 2008.

The team found that strong, long, and recurring high-speed streams of charged particles buffeted Earth in 2008. In contrast, Earth encountered weaker and more sporadic streams in 1996. As a result, the planet was more affected by the sun in 2008 than in 1996, as measured by such variables as the strength of electron fluxes in the outer radiation belt, the velocity of the solar wind in the vicinity of Earth, and the periodic behavior of auroras (the Northern and Southern lights) as they responded to repeated high-speed streams.

The prevalence of high-speed streams during this solar minimum appears to be related to the current structure of the sun. As sunspots became less common over the last few years, large coronal holes lingered in the surface of the sun near its equator. The high-speed streams that blow out of those holes engulfed Earth during 55 percent of the study period in 2008, compared to 31 percent of the study period in 1996. A single stream of charged particles can last for as long as seven to 10 days. At their peak, the accumulated impact of the streams during one year can inject as much energy into Earth's environment as massive eruptions from the sun's surface can during a year at the peak of a solar cycle, says co-author Janet Kozyra of the University of Michigan.

The streams strike Earth periodically, spraying out in full force like water from a fire hose as the sun revolves. When the magnetic fields in the solar winds point in a direction opposite to the magnetic lines in Earth's magnetosphere, they have their strongest effect. The strength and speed of the magnetic fields in the high-speed streams can also affect Earth's response.

The authors speculate that the high number of low-latitude coronal holes during this solar minimum may be related to a weakness in the sun's overall magnetic field. The sun in 2008 had smaller polar coronal holes than in 1996, but high-speed streams that escape from the sun's poles do not travel in the direction of Earth.

"The sun-Earth interaction is complex, and we haven't yet discovered all the consequences for the Earth's environment of the unusual solar winds this cycle," Kozyra says. "The intensity of magnetic activity at Earth in this extremely quiet solar minimum surprised us all. The new observations from last year are changing our understanding of how solar quiet intervals affect the Earth and how and why this might change from cycle to cycle."

-NSF-

Media Contacts

Cheryl Dybas, NSF (703) 292-7734
cdybas@nsf.gov
David Hosansky, NCAR (303) 497-8611 hosansky@ucar.edu
Peter Weiss, American Geophysical Union (202) 777-7507 pweiss@agu.org

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2009, its budget is $9.5 billion, which includes $3.0 billion provided through the American Recovery and Reinvestment Act. NSF funds reach all 50 states through grants to over 1,900 universities and institutions. Each year, NSF receives about 44,400 competitive requests for funding, and makes over 11,500 new funding awards. NSF also awards over $400 million in professional and service contracts yearly.

Thursday, November 13, 2008

Don Easterbrook on Global Cooling

This is an excellent article presenting the evidence for the onset of global cooling. That it is an extrapolation of past cycles over a claimed period of several hundred years is unconvincing since our data is very spotty after we go a hundred and fifty years back. I would even assert it is spotty up to the beginning of the satellite age.

We comfortably know a few things as we go back in time and very little outside of major centers. I am very conscious of how local weather is in the face of minimal communication between observers.

Therefore I get nervous as we attempt to link various proxies together.

In the meantime the arguments for global cooling are quite solid compared to the IPCC projections which have been just plain wrong. They did not even get lucky. I swear that I could give them three to one odds for flipping coins and still win. Ten years of flat temperature change is a pretty good endorsement for the failure of a model claiming an uptrend.

We now have had a major down draft in the apparent temperature regime that must mean something if it is not a herald of many cold winters. Also the Alaska glaciers were net gainers of snow this past season. Thus we can expect the glaciers to advance shortly.

I am going to miss seeing an ice free Arctic it seems.

I must remark that the evidence is certainly mounting that the deep freeze is in the process of returning to the Arctic. It really has not actually hit the sea ice yet but it should deliver a sharp increase in thickness this winter if it has actually gotten colder. Again all we can do is wait and see.



Global Cooling is Here
Evidence for Predicting Global Cooling for the Next Three Decades

by Prof. Don J. Easterbrook

Global Research, November 2, 2008

Department of Geology, Western Washington University

Global Research Editor's note

The following article represents an alternative view and analysis of global climate change, which challenges the dominant Global Warming Consensus.

Global Research does not necessarily endorse the proposition of "Global Cooling", nor does it accept at face value the Consensus on Global Warming. Our purpose is to encourage a more balanced debate on the topic of global climate change.

INTRODUCTION

Despite no global warming in 10 years and recording setting cold in 2007-2008, the Intergovernmental Panel on Climatic Change (IPCC) and computer modelers who believe that CO2 is the cause of global warming still predict the Earth is in store for catastrophic warming in this century. IPCC computer models have predicted global warming of 1° F per decade and 5-6° C (10-11° F) by 2100 (Fig. 1), which would cause global catastrophe with ramifications for human life, natural habitat, energy and water resources, and food production. All of this is predicated on the assumption that global warming is caused by increasing atmospheric CO2 and that CO2 will continue to rise rapidly.

http://www.globalresearch.ca/articlePictures/glcool1.jpg
http://www.globalresearch.ca/articlePictures/globalcool2.jpg


Figure 1. A. IPCC prediction of global warming early in the 21st century. B. IPCC prediction of global warming to 2100. (Sources: IPCC website)

However, records of past climate changes suggest an altogether different scenario for the 21st century. Rather than drastic global warming at a rate of 0.5 ° C (1° F) per decade, historic records of past natural cycles suggest global cooling for the first several decades of the 21st century to about 2030, followed by global warming from about 2030 to about 2060, and renewed global cooling from 2060 to 2090 (Easterbrook, D.J., 2005, 2006a, b, 2007, 2008a, b); Easterbrook and Kovanen, 2000, 2001). Climatic fluctuations over the past several hundred years suggest ~30 year climatic cycles of global warming and cooling, on a general rising trend from the Little Ice Age.

PREDICTIONS BASED ON PAST CLIMATE PATTERNS

Global climate changes have been far more intense (12 to 20 times as intense in some cases) than the global warming of the past century, and they took place in as little as 20–100 years. Global warming of the past century (0.8° C) is virtually insignificant when compared to the magnitude of at least 10 global climate changes in the past 15,000 years. None of these sudden global climate changes could possibly have been caused by human CO2 input to the atmosphere because they all took place long before anthropogenic CO2 emissions began. The cause of the ten earlier ‘natural’ climate changes was most likely the same as the cause of global warming from 1977 to 1998.

Figure 2. Climate changes in the past 17,000 years from the GISP2 Greenland ice core. Red = warming, blue = cooling. (Modified from Cuffy and Clow, 1997)

Climatic fluctuations over the past several hundred years suggest ~30 year climatic cycles of global warming and cooling (Figure 3) on a generally rising trend from the Little Ice Age about 500 years ago.

Figure 3. Alternating warm and cool cycles since 1470 AD. Blue = cool, red = warm. Based on oxygen isotope ratios from the GISP2 Greenland ice core.

Relationships between glacial fluctuations, the Pacific Decadal Oscillation, and global climate change.
After several decades of studying alpine glacier fluctuations in the North Cascade Range, my research showed a distinct pattern of glacial advances and retreats (the Glacial Decadal Oscillation, GDO) that correlated well with climate records. In 1992, Mantua published the Pacific Decadal Oscillation curve showing warming and cooling of the Pacific Ocean that correlated remarkably well with glacial fluctuations. Both the GDA and the PDO matched global temperature records and were obviously related (Fig. 4). All but the latest 30 years of changes occurred prior to significant CO2 emissions so they were clearly unrelated to atmospheric CO2.

http://www.globalresearch.ca/articlePictures/globalcool5.jpg

Figure 4. Correspondence of the GDO, PDO, and global temperature variations.

The significance of the correlation between the GDO, PDO, and global temperature is that once this connection has been made, climatic changes during the past century can be understood, and the pattern of glacial and climatic fluctuations over the past millennia can be reconstructed. These patterns can then be used to project climatic changes in the future. Using the pattern established for the past several hundred years, in 1998 I projected the temperature curve for the past century into the next century and came up with curve ‘A’ in Figure 5 as an approximation of what might be in store for the world if the pattern of past climate changes continued. Ironically, that prediction was made in the warmest year of the past three decades and at the acme of the 1977-1998 warm period. At that time, the projected curved indicated global cooling beginning about 2005 ± 3-5 years until about 2030, then renewed warming from about 2030 to about 2060 (unrelated to CO2—just continuation of the natural cycle), then another cool period from about 2060 to about 2090. This was admittedly an approximation, but it was radically different from the 1° F per decade warming called for by the IPCC. Because the prediction was so different from the IPCC prediction, time would obviously show which projection was ultimately correct.

Now a decade later, the global climate has not warmed 1° F as forecast by the IPCC but has cooled slightly until 2007-08 when global temperatures turned sharply downward. In 2008, NASA satellite imagery (Figure 6) confirmed that the Pacific Ocean had switched from the warm mode it had been in since 1977 to its cool mode, similar to that of the 1945-1977 global cooling period. The shift strongly suggests that the next several decades will be cooler, not warmer as predicted by the IPCC.

http://www.globalresearch.ca/articlePictures/globalcool61.jp

Figure 5. Global temperature projection for the coming century, based on warming/cooling cycles of the past several centuries. ‘A’ projection based on assuming next cool phase will be similar to the 1945-1977 cool phase. ‘B’ projection based on assuming next cool phase will be similar to the 1880-1915 cool phase. The predicted warm cycle from 2030 to 2060 is based on projection of the 1977 to 1998 warm phase and the cooling phase from 2060 to 2090 is based on projection of the 1945 to 1977 cool cycle.

Implications of PDO, NAO, GDO, and sun spot cycles for global climate in coming decades

The IPCC prediction of global temperatures, 1° F warmer by 2011 and 2° F by 2038 (Fig. 1), stand little chance of being correct. NASA’s imagery showing that the Pacific Decadal Oscillation (PDO) has shifted to its cool phase is right on schedule as predicted by past climate and PDO changes (Easterbrook, 2001, 2006, 2007). The PDO typically lasts 25-30 years and assures North America of cool, wetter climates during its cool phases and warmer, drier climates during its warm phases. The establishment of the cool PDO, together with similar cooling of the North Atlantic Oscillation (NAO), virtually assures several decades of global cooling and the end of the past 30-year warm phase. It also means that the IPCC predictions of catastrophic global warming this century were highly inaccurate.

The switch of PDO cool mode to warm mode in 1977 initiated several decades of global warming. The PDO has now switched from its warm mode (where it had been since 1977) into its cool mode. As shown on the graph above, each time this had happened in the past century, global temperature has followed. The upper map shows cool ocean temperatures in blue (note the North American west coast). The lower diagram shows how the PDO has switched back and forth from warm to cool modes in the past century, each time causing global temperature to follow. Comparisons of historic global climate warming and cooling over the past century with PDO and NAO oscillations, glacial fluctuations, and sun spot activity show strong correlations and provide a solid data base for future climate change projections.

The Pacific Ocean has a warm temperature mode and a cool temperature mode, and in the past century, has switched back forth between these two modes every 25-30 years (known as the Pacific Decadal Oscillation or PDO). In 1977 the Pacific abruptly shifted from its cool mode (where it had been since about 1945) into its warm mode, and this initiated global warming from 1977 to 1998. The correlation between the PDO and global climate is well established. The announcement by NASA’s Jet Propulsion Laboratory that the Pacific Decadal Oscillation (PDO) had shifted to its cool phase is right on schedule as predicted by past climate and PDO changes (Easterbrook, 2001, 2006, 2007). The PDO typically lasts 25-30 years and assures North America of cool, wetter climates during its cool phases and warmer, drier climates during its warm phases. The establishment of the cool PDO, together with similar cooling of the North Atlantic Oscillation (NAO), virtually assures several decades of global cooling and the end of the past 30-year warm phase.

Figure 6. Switch of PDO cool mode to warm mode in 1977 initiated several decades of global warming. The PDO has now switched from its warm mode (where it had been since 1977) into its cool mode. As shown on the graph above, each time this has happened in the past century, global temperature has followed. The upper map shows cool ocean temperatures in blue (note the North American west coast). The lower diagram shows how the PDO has switched back and forth from warm to cool modes in the past century, each time causing global temperature to follow. Projection of the past pattern (right end of graph) assures 30 yrs of global cooling

Comparisons of historic global climate warming and cooling over the past century with PDO and NAO oscillations, glacial fluctuations, and sun spot activity show strong correlations and provide a solid data base for future climate change projections. As shown by the historic pattern of GDOs and PDOs over the past century and by corresponding global warming and cooling, the pattern is part of ongoing warm/cool cycles that last 25-30 years. The global cooling phase from 1880 to 1910, characterized by advance of glaciers worldwide, was followed by a shift to the warm-phase PDO for 30 years, global warming and rapid glacier recession. The cool-phase PDO returned in ~1945 accompanied by global cooling and glacial advance for 30 years. Shift to the warm-phase PDO in 1977 initiated global warming and recession of glaciers that persisted until 1998. Recent establishment of the PDO cool phase appeared right on target and assuming that its effect will be similar to past history, global climates can be expected to cool over the next 25-30 years. The global warming of this century is exactly in phase with the normal climatic pattern of cyclic warming and cooling and we have now switched from a warm phase to a cool phase right at the predicted time (Fig. 5)
The ramifications of the global cooling cycle for the next 30 years are far reaching―e.g., failure of crops in critical agricultural areas (it’s already happening this year), increasing energy demands, transportation difficulties, and habitat change. All this during which global population will increase from six billion to about nine billion. The real danger in spending trillions of dollars trying to reduce atmospheric CO2 is that little will be left to deal with the very real problems engendered by global cooling.

CONCLUSIONS

Global warming (i.e, the warming since 1977) is over. The minute increase of anthropogenic CO2 in the atmosphere (0.008%) was not the cause of the warming—it was a continuation of natural cycles that occurred over the past 500 years.

The PDO cool mode has replaced the warm mode in the Pacific Ocean, virtually assuring us of about 30 years of global cooling, perhaps much deeper than the global cooling from about 1945 to 1977. Just how much cooler the global climate will be during this cool cycle is uncertain. Recent solar changes suggest that it could be fairly severe, perhaps more like the 1880 to 1915 cool cycle than the more moderate 1945-1977 cool cycle. A more drastic cooling, similar to that during the Dalton and Maunder minimums, could plunge the Earth into another Little Ice Age, but only time will tell if that is likely.

Don J. Easterbrook is Professor of Geology at Western Washington University. Bellingham, WA.

Thursday, June 5, 2008

David Archibald on Solar Variation

David Archibald has given us this very detailed paper on historical global climate and focuses on the role of solar activity. This is as complete a workout of the issues as I have so far seen.

http://www.lavoisier.com.au/papers/Conf2007/Archibald2007.pdf

Although he goes back through geologic time and produces the appropriate graphs, most of the data is hardly settled and certainly subject to and has been subject to ongoing debate and access to new proxies.

It is unfortunate but any proxy that can be projected to directly reflect temperatures, can also be modified almost randomly by other factors and we have no way to properly correct for this. The second problem is that once one draws a line between two points it is impossible to avoid thinking that this is a continuous process that is been measured. Yet climate is famously discontinuous

In any event, this is still a nice presentation, but do not get comfortable that any of this is all settled. More importantly, the Pleistocene Nonconformity has changed everything that has gone before inasmuch as the variation range of global temperature has been hugely narrowed. Therefore a look at the implied variation range for the past millions of years is misleading in the context of the Holocene.

What has been in fact remarkable has been the implied two degree range maintained for the past ten thousand years.

Archibald lays out the argument for the direct involvement of solar activity in driving the heat content of the atmosphere. He also spells out the nature of the current apparent slow onset of solar cycle number 24. His work is well done, and he argues forcefully for a major two degree drop over the next twenty years very similar to the Dalton minimum.

He also puts the contribution of CO2 to global warming into complete perspective and the result is negligible, largely because any response is logarithmic rather than linear and at best is good for a tenth of a degree. Solar variation appears to be able to produce variation over two degrees, several times any Anthropogenic effect.

This paper is well worth the read as it pulls together the total argument for the importance of solar variation and attempts to place it all in a continuous narrative that may be full of gaping holes but is at least making the attempt. This is much better than the many studies that usually focus on a narrow window of results and assume a position outside that window.

______________________________________

This short item gives the accepted opinion on solar variation.


Solar Variability: Striking a Balance with Climate Change

05.07.08

Credit: NASA Goddard Space Flight Center The sun has powered almost everything on Earth since life began, including its climate. The sun also delivers an annual and seasonal impact, changing the character of each hemisphere as Earth's orientation shifts through the year. Since the Industrial Revolution, however, new forces have begun to exert significant influence on Earth's climate.

"For the last 20 to 30 years, we believe greenhouse gases have been the dominant influence on recent climate change," said Robert Cahalan, climatologist at NASA’s Goddard Space Flight Center in Greenbelt, Md.

For the past three decades NASA scientists have investigated the unique relationship between the sun and Earth. Using space-based tools, like the Solar Radiation and Climate Experiment (SORCE), they have studied how much solar energy illuminates Earth, and explored what happens to that energy once it penetrates the atmosphere. The amount of energy that reaches Earth's outer atmosphere is called the total solar irradiance. Total solar irradiance is variable over many different timescales, ranging from seconds to centuries due to changes in solar activity.

The sun goes through roughly an 11-year cycle of activity, from stormy to quiet and back again. Solar activity often occurs near sunspots, dark regions on the sun caused by concentrated magnetic fields. The solar irradiance measurement is much higher during solar maximum, when sunspot cycle and solar activity is high, versus solar minimum, when the sun is quiet and there are usually no sunspots.
The sun radiates huge amounts of electromagnetic energy in all directions. Earth is only one small recipient of the sun's energy; the sun's rays extend far out into the solar system, illuminating all the other planets. Credit: NASA

"The fluctuations in the solar cycle impacts Earth's global temperature by about 0.1 degree Celsius, slightly hotter during solar maximum and cooler during solar minimum," said Thomas Woods, solar scientist at the University of Colorado in Boulder. "The sun is currently at its minimum, and the next solar maximum is expected in 2012."

Using SORCE, scientists have learned that about 1,361 watts per square meter of solar energy reaches Earth's outermost atmosphere during the sun's quietest period. But when the sun is active, 1.3 watts per square meter (0.1 percent) more energy reaches Earth. "This TSI measurement is very important to climate models that are trying to assess Earth-based forces on climate change," said Cahalan.

Over the past century, Earth's average temperature has increased by approximately 0.6 degrees Celsius (1.1 degrees Fahrenheit). Solar heating accounts for about 0.15 C, or 25 percent, of this change, according to computer modeling results published by NASA Goddard Institute for Space Studies researcher David Rind in 2004. Earth's climate depends on the delicate balance between incoming solar radiation, outgoing thermal radiation and the composition of Earth's atmosphere. Even small changes in these parameters can affect climate. Around 30 percent of the solar energy that strikes Earth is reflected back into space. Clouds, atmospheric aerosols, snow, ice, sand, ocean surface and even rooftops play a role in deflecting the incoming rays. The remaining 70 percent of solar energy is absorbed by land, ocean, and atmosphere.

"Greenhouse gases block about 40 percent of outgoing thermal radiation that emanates from Earth," Woods said. The resulting imbalance between incoming solar radiation and outgoing thermal radiation will likely cause Earth to heat up over the next century, accelerating the melting polar ice caps, causing sea levels to rise and increasing the probability of more violent global weather patterns.

Non-Human Influences on Climate Change

Before the Industrial Age, the sun and volcanic eruptions were the major influences on Earth's climate change. Earth warmed and cooled in cycles. Major cool periods were ice ages, with the most recent ending about 11,000 years ago.

"Right now, we are in between major ice ages, in a period that has been called the Holocene,” said Cahalan. “Over recent decades, however, we have moved into a human-dominated climate that some have termed the Anthropocene. The major change in Earth's climate is now really dominated by human activity, which has never happened before."

The sun is relatively calm compared to other stars. "We don't know what the sun is going to do a hundred years from now," said Doug Rabin, a solar physicist at Goddard. "It could be considerably more active and therefore have more influence on Earth's climate."Or, it could be calmer, creating a cooler climate on Earth similar to what happened in the late 17th century. Almost no sunspots were observed on the sun's surface during the period from 1650 to 1715. This extended absence of solar activity may have been partly responsible for the Little Ice Age in Europe and may reflect cyclic or irregular changes in the sun's output over hundreds of years. During this period, winters in Europe were longer and colder by about 1 C than they are today.

Since then, there seems to have been on average a slow increase in solar activity. Unless we find a way to reduce the amount of greenhouse gases we put into the atmosphere, such as carbon dioxide from fossil fuel burning, the solar influence is not expected to dominate climate change. But the solar variations are expected to continue to modulate both warming and cooling trends at the level of 0.1 to 0.2 degrees Celsius (0.18 to 0.26 Fahrenheit) over many years.

Future Measurements of Solar Variability

For three decades, a suite of NASA and European Space Agency satellites have provided scientists with critical measurements of total solar irradiance. The Total Irradiance Monitor, also known as the TIM instrument, was launched in 2003 as part of the NASA’s SORCE mission, and provides irradiance measurements with state-of-the-art accuracy. TIM has been rebuilt as part of the Glory mission, scheduled to launch in 2009. Glory's TIM instrument will continue an uninterrupted 30-year record of solar irradiance measurements and will help researchers better understand the sun's direct and indirect effects on climate. Glory will also collect data on aerosols, one of the least understood pieces of the climate puzzle.

Wednesday, July 18, 2007

Good article on global warming model

This is a good review on the limitations of our global warming theory.

This article nicely underlines my core misgivings on our linkage of CO2 emissions with the apparent phenomena of global warming which far too easily could turn out to be simply wrong.

What is not wrong is the fact that nature is unable to currently absorb the huge amount of CO2 we are producing by burning fossil fuels. This problem must be solved.in its own right.

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