Saturday 30th of March 2024

albedo...

albedo

There is controversy about climate change...  Yet, the serious scientists in both camps have clearly established that the surface of the earth has been warming up...

This warming is estimated at a certain amount (0.1 degrees C average) per decade (now around 0.2 degree C) for the last 150 years... Gus' present estimate is for a full one (1) degree C increase for the next 10 year. I could be wrong, but considering the sun is awakening and El Nino is about to come back, I may be right.

Most of the controversy is centred on the origin of this warming.

Up until the industrial revolution, humans used mostly surface available carbon such as wood from trees and a little oil from tar pits and a little coal from shallow mines.
Humans had had only a limited natural impact on the planet till then. 
Then came "fossil fuels". The usage of fossil fuels releases carbon dioxide into the atmosphere, adding to the natural carbon equation with carbon that had been sequestered as far back as the Carboniferous (350 -300 million years ago approx). Though much of this carbon is still sequestering naturally today, 3 to 6 ppm of CO2 per annum is not sequestered and remains in the atmosphere. 
Since the industrial revolution, humans have added about 125 ppm of CO2 in the atmosphere. (Gus' figure)
knowing versus using...
One of the tremendous ability of our species is to ask questions and analyse on who we are and where we are.
For the last 120 years, science has made some extraordinary strides and daily there are new discoveries or new ideas, most refining our knowledge away from fantasies — as proposed by religions. Science is not a religion.
And science has made mistakes, has often recognised its errors and in some areas scientists have had some vigourous debate trying to reconcile observation and theory. Global warming is not one of those blunders... Global warming science, despite some "uncertainties about the next effects", is 99.9 per cent accurate on the origins. Most (more than 95 per cent) scientists know that human burning of fossil fuels is inducing global warming. But the minority of the scientists disputing this theory get the bigger slice of the media's attention.
The major problem here is that human's present endeavours rely nearly exclusively on burning fossil fuels... There is a lot of cash to be made in selling fossil fuel energy and there is no monetary value in reducing our usage of fossil fuels. Greed trumps knowledge...
We live on a relatively small planet upon which our growing population is having a growing enormous impact on the surface environment from cultivation to industries, husbandry to polluting.
Albedo
One of the observation/theory conundrum relates to albedo or the reflectance of sun heat from planets back into the cosmos. This of course has a bearing on the earth's "global warming", which is presently observed... A light coloured surface will reflect more than a dark coloured surface, thus a light coloured surface is likely to make a planet "cooler"... 
These characteristics have been calculated with remarkable precision and a lot of scientific work has been done to tell us that presently (this now is important) due to the albedo the average temperature of the earth is around 15 degrees C. Should the earth be covered in ice (high reflectance) the temperature would drop below minus 40 degrees C. Should the earth be covered by oceans (lower reflectance/ more absorption of heat), the surface temperature of this planet would be around 27 degrees C. All this albedo calculated without change in the gaseous mix of the atmosphere.
One of the main variable when studying global warming and albedo is the presence of clouds (opaque water vapour). Some clouds will have a high albedo (high degree of reflectance) while some clouds will have a low albedo (despite being white, they let heat and light through, and trap infrared radiation below). Thus albedo of clouds can range from low (0.1) equivalent to asphalt to high (0.9) equivalent to snow...
Thus any global warming calculation need to take into account the albedo average for the surface of the earth — at various times — due to cloud cover, or not — and the melting of the ice that decreases the albedo, yet absorbs energy away from the atmosphere to melt in a complex feed-back-plus mechanism (I call a feed-back-plus mechanism a mechanism in which extra input is added into the feed-back loop.
About 4 billion years ago was what has been called the "faint sun paradox"... It has been calculated by some serious scientists that the earth then would have been mostly covered with water. The albedo would have been sufficiently low to counteract a much cooler sun. Since that time, the sun's intensity has grown 25 to 30 per cent. This is in line with observation/calculation of "evolving" stars. 
Thus the scientists estimated with a high degree of precision/calculations that despite the cooler sun, the earth did not freeze over, but enjoyed similar temperatures as today. The albedo of the ocean reflectance was enough to maintain this temperature. Greenhouse gases would have been needed in super-high concentrations in order to achieve a similar result — concentrations that do not appear in the geological record — hence the so-called "paradox".
The atmosphere albedo (reflectance of the sun heat) is about 0.3 (30 per cent) on average.
The seasonal variation do also affect the albedo greatly, especially in regard to oceans covering more of the southern hemisphere than the northern hemisphere...
There has also been specific studies of the geological record that show on average, CO2 amount in the atmosphere and the earth surface temperatures are "dancing" together, once other factors such as proportion of oxygen (a cooling gas) in the gaseous mix is taken into account. For example Arrhenius calculated that the last ice age saw about 45 per cent less CO2 that there was in 1890. Presently we have MORE THAN 200 per cent on the amount of CO2 in 1890. 
It has been demonstrated that CO2 is a gas that absorbs infrared radiation (thus greenhouse warming). It has been postulated that CO2 also affects the behaviour of water in the atmosphere. Gus says: Imagine adding a drop of dishwashing liquid in a bucket of water... Suddenly, the "surface" water tension is modified RIGHT THROUGHOUT THE BUCKET...  CO2 might be possibly changing the dew point at which water vapour becomes cloudy or not. A slight variation of the dew point will change the level at which cloudiness occurs. In contrast, more heat also means more evaporation (from the sea) which means higher humidity which in turns can change the dew point to create low but "warmer" clouds.  (Some scientists describe CO2 as a "trigger" mechanism)...
A storm will have a high reflectance, thus lower temperatures below it but higher temperatures around it plus the Coriolis force can turn such differential into a fierce hurricane, cyclone or typhoon. Other storms are generated from the interface of warm and cool air masses. The most severe of such interface results in tornadoes.
As the surface of the globe is warming up, what can we make of all this? In most of the record from about 1 million years ago, we can see that a difference of CO2 from 100 ppm to 300 ppm is "always" associated with a difference of temperature of up to 8 degrees C (10.5 according to some serious journals)...
100 ppm to 300 ppm of CO2 is in the realm of "natural" atmospheric carbon equation. Fires, trees, seas in cycles of photosynthesis, absorption and release. Yet the temperatures are linked to this cycle via the behaviour of the atmosphere in the lowest 10,000 metres, where water vapour (a greenhouse gas) can be either cloudy or clear... changing the albedo, in a loop until a new cycle begins... 
Presently due to human activities, the atmospheric CO2 level is around 410 ppm. You work it out. 
(Updated 2 july 2019).

here comes the maths...

albedocalculus

less albedo... more heat...

 

They described the event as being without precedent, because such a massive loss of ice has not been observed by humans, although estimates derived from studying old, compressed ice suggest that melts on this scale happen about once every 150 years.
''Researchers have not yet determined whether this extensive melt event will affect the overall volume of ice loss this summer and contribute to sea-level rise,'' NASA said. ''About one-fifth of the annual sea-level rise experienced globally is attributed to the melting of the ice sheet.''
The manager of Australia's climate monitoring section at the Bureau of Meteorology, Karl Braganza, said the observation was a disturbing development.
''In terms of just one event taken in isolation, you can't tell much from it. We had a similar event back in the 1800s so it does happen from time to time,'' Dr Braganza said.
''But clearly there is a trend going on in the Arctic this century. We have warmer ocean temperatures, now what looks like particularly large reductions in sea ice, and large chunks of glaciers breaking off.''
The Arctic appeared to be locked in a vicious cycle, where rising concentrations of greenhouse gases meant higher temperatures, and more melting ice, which meant, in turn, that less of the sun's incoming heat was reflected away from the Earth.
''What's alarming to scientists is that we know the Arctic ice is a key feedback, and the warming in the Arctic has been slightly faster than was predicted 10 or 20 years ago,'' Dr Braganza said.

Read more: http://www.smh.com.au/technology/sci-tech/greenland-melts-before-nasas-eyes-20120725-22qtb.html#ixzz21jBX9frT
read article at top 

 

albedo change from ice melt...

 

... results from the European Space Agency's CryoSat-2 probe indicate that 900 cubic kilometres of summer sea ice has disappeared from the Arctic ocean over the past year.

This rate of loss is 50% higher than most scenarios outlined by polar scientists and suggests that global warming, triggered by rising greenhouse gas emissions, is beginning to have a major impact on the region. In a few years the Arctic ocean could be free of ice in summer, triggering a rush to exploit its fish stocks, oil, minerals and sea routes.

Using instruments on earlier satellites, scientists could see that the area covered by summer sea ice in the Arctic has been dwindling rapidly. But the new measurements indicate that this ice has been thinning dramatically at the same time. For example, in regions north of Canada and Greenland, where ice thickness regularly stayed at around five to six metres in summer a decade ago, levels have dropped to one to three metres.

"Preliminary analysis of our data indicates that the rate of loss of sea ice volume in summer in the Arctic may be far larger than we had previously suspected," said Dr Seymour Laxon, of the Centre for Polar Observation and Modelling at University College London (UCL), where CryoSat-2 data is being analysed. "Very soon we may experience the iconic moment when, one day in the summer, we look at satellite images and see no sea ice coverage in the Arctic, just open water."

The consequences of losing the Arctic's ice coverage, even for only part of the year, could be profound. Without the cap's white brilliance to reflect sunlight back into space, the region will heat up even more than at present. As a result, ocean temperatures will rise and methane deposits on the ocean floor could melt, evaporate and bubble into the atmosphere. Scientists have recently reported evidence that methane plumes are now appearing in many areas. Methane is a particularly powerful greenhouse gas and rising levels of it in the atmosphere are only likely to accelerate global warming. And with the disappearance of sea ice around the shores of Greenland, its glaciers could melt faster and raise sea levels even more rapidly than at present.

http://www.guardian.co.uk/environment/2012/aug/11/arctic-sea-ice-vanishing

 

losing ice at the bottom of the world...

The vast expanse of sea ice around Antarctica has suffered a “precipitous” fall since 2014, satellite data shows, and fell at a faster rate than seen in the Arctic.

The plunge in the average annual extent means Antarctica lost as much sea ice in four years as the Arctic lost in 34 years. The cause of the sharp Antarctic losses is as yet unknown and only time will tell whether the ice recovers or continues to decline.

But researchers said it showed ice could disappear much more rapidly than previously thought. Unlike the melting of ice sheets on land, sea ice melting does not raise sea level. But losing bright white sea ice means the sun’s heat is instead absorbed by dark ocean waters, leading to a vicious circle of heating.

Sea ice spreads over enormous areas and has major impacts on the global climate system, with losses in the Arctic strongly linked to extreme weather at lower latitudes, such as heatwaves in Europe.

 

Read more:

https://www.theguardian.com/world/2019/jul/01/precipitous-fall-in-antarc...

 

Read from top.

 

See also: 

http://www.yourdemocracy.net.au/drupal/node/36434

 

longyearbyen is warming up

...

Nowhere on the planet is heating faster. This was the message of a report commissioned by the Norwegian Environment Agency, unveiled in February to a stunned audience in Longyearbyen, the archipelago’s de facto capital. People knew things were bad, but it was only when they heard the forecast that they realised how bad. A local reporter described how people at the meeting fell silent when they heard the statistics, which sounded like the “gloomy horror scenario of a bad thriller”.

Since 1971, temperatures here have risen by 4C, five times faster than the global average. In the winter, when the changes are more marked, it has gone up by an astonishing 7C. These are increases that the rest of the world is not expected to experience until the 22nd century. They are far ahead of most computer simulations. Yet there is still more to come. On current trends, Svalbard will hit 10C of warming by 2100.

Read more:

https://www.theguardian.com/environment/ng-interactive/2019/jul/01/its-g...

 

Read from top.

 

See also:

http://www.yourdemocracy.net.au/drupal/node/36667

 

http://www.yourdemocracy.net.au/drupal/node/1048

 

Note: The article in the Guardian is supported by the David and Lucile Packard Foundation:

The David and Lucile Packard Foundation is a private foundation that provides grants to not-for-profit organizations. It was created in 1964 by David Packard (co-founder of HP) and his wife Lucile Salter Packard. Following David Packard's death in 1996, the Foundation became the beneficiary of part of his estate. The foundation's goals, through the use of grants, are to "improve the lives of children, enable creative pursuit of science, advance reproductive health, and conserve and restore earth’s natural systems.[3]" As of 2016, The David and Lucile Packard Foundation was the 20th wealthiest foundation in the United States.

...

The majority of grants are distributed among four main program areas: Conservation and Science; Population and Reproductive Health; Children, Families, and Communities; and Local Grantmaking.[3]The Foundation also deploys Mission Investments to expand the impact of grantmaking by making loans and equity investments to further programmatic goals.

Read more:

https://en.wikipedia.org/wiki/David_and_Lucile_Packard_Foundation