Tag: Clouds

Diesel , Lightning , Ships and Clouds

Published on by sunshinehours14 Comments

If true this makes a huge case for eliminating diesel and switching to Natural Gas for shipping.

“The new study is the first to show ship exhaust can alter thunderstorm intensity. The researchers conclude that particles from ship exhaust make cloud droplets smaller, lifting them higher in the atmosphere. This creates more ice particles and leads to more lightning.

The results provide some of the first evidence that humans are changing cloud formation on a nearly continual basis, rather than after a specific incident like a wildfire, according to the authors. Cloud formation can affect rainfall patterns and alter climate by changing how much sunlight clouds reflect to space.

“It’s one of the clearest examples of how humans are actually changing the intensity of storm processes on Earth through the emission of particulates from combustion,” said Joel Thornton, an atmospheric scientist at the University of Washington in Seattle and lead author of the new study in Geophysical Research Letters, a journal of the American Geophysical Union.

“It is the first time we have, literally, a smoking gun, showing over pristine ocean areas that the lightning amount is more than doubling,” said Daniel Rosenfeld, an atmospheric scientist at the Hebrew University of Jerusalem who was not connected to the study. “The study shows, highly unambiguously, the relationship between anthropogenic emissions — in this case, from diesel engines — on deep convective clouds.””

Lightning

“In the new study, co-author Katrina Virts, an atmospheric scientist at NASA Marshall Space Flight Center in Huntsville, Alabama, was analyzing data from the World Wide Lightning Location Network, a network of sensors that locates lightning strokes all over the globe, when she noticed a nearly straight line of lightning strokes across the Indian Ocean.

Virts and her colleagues compared the lightning location data to maps of ships’ exhaust plumes from a global database of ship emissions. Looking at the locations of 1.5 billion lightning strokes from 2005 to 2016, the team found nearly twice as many lightning strokes on average over major routes ships take across the northern Indian Ocean, through the Strait of Malacca and into the South China Sea, compared to adjacent areas of the ocean that have similar climates.

More than $5 trillion of world trade passes through the South China Sea every year and nearly 100,000 ships pass through the Strait of Malacca alone. Lightning is a measure of storm intensity, and the researchers detected the uptick in lightning at least as far back as 2005.

“All we had to do was make a map of where the lightning was enhanced and a map of where the ships are travelling and it was pretty obvious just from the co-location of both of those that the ships were somehow involved in enhancing lightning,” Thornton said.”

Global Warming May Have Been Caused By Deforestation

Published on by sunshinehours12 Comments

Yesterday I wrote about trees being able to seed clouds. Lubos of the Reference Frame takes it further.

It’s been generally thought that the sulfuric acid was almost necessary. Chimneys (or volcano eruptions etc.) should increase cloudiness. However, there have been inconclusive hints in some papers that some organic molecules are enough. You may have worried: How could have the clouds existed in the past, before the chimneys were built? 😉

Jasper Kirkby and collaborators have found out that the molecules known as “aroma of the trees” may indeed do the same job and that is decisive in the pristine environments without chimneys.

More precisely, the molecules that can do the job are the “highly oxygenated molecules” (HOMs) which are produced by ozonolysis of α-pinene.

The lesson for “global warming” seems clear: deforestation may decrease the amount of aroma from the trees, and therefore the amount of clouds, and it may therefore lead to global warming.

This may be the explanation of the changes in the 20th century and because the deforestation is over, so may be “global warming”.

 

So … what other periods of global warming took place?

“The Roman Warm Period or the Roman climatic optimum has been proposed as a period of unusually warm weather in Europe and the North Atlantic that ran from approximately 250 BC to 400 AD”

What is Rome famous for (other than killing and conquering and so on)? Roman baths. What did the heat the baths with? Firewood.

“The baths were BIG; the Baths of Caracalla, completed in 235, could handle 8,000 visitors a day. Its 50 furnaces burned ten tons of wood every day to keep the water warm.

Deforestation was huge in Roman times.

Wood was a primary source of heating and used extensively in industry. Wood fuel constituted about 90 percent of the consumption overall,[citation needed] and was a major factor in Roman deforestation. Wood was essential fuel in industries like mining, smelting, and the making of ceramics.[4] Wood and charcoal were the primary ancient fuels in public facilities, households, public baths and industries that produced light and heat.

Forest areas around mining centers were deforested first, consuming all natural resources around the area of work. Once all the natural resources around the area of production were consumed, wood was then shipped and carried in to supply the furnaces and smelters for the mining centers. Eventually, these centers would shut down and move to areas within Roman territory to repeat the same cycle of deforestation, supplying an ever-growing population and consumption demand.

Deforestation and the fall of Rome :

In the ancient world, fossil fuels were unusual enough to be a curiosity, and certainly did not provide any major heating source. Almost all heating was done by wood and wood products1and while it may not seem like such a major factor it becomes a different story if you think about the Roman baths. The public baths2 were kept constantly at a minimum of 130 degrees Fahrenheit (54 degrees Celsius), and even a very small bath required 228,000lb (103,421kg) of wood per year. The Emperors recognised the importance of the baths in keeping the populace happy, and made keeping them running a primary goal. A whole guild, equipped with 60 ships, was created specifically for the purpose of obtaining bath-heating wood. Large palaces and villas also often had personal central heating systems; one such system has been evaluated and determined to require 2,506,000lb (1,136,722kg) of wood per year in order to properly heat the villa.

Trees Can Seed Clouds!

Published on by sunshinehours15 Comments

This discovery is huge. Trees can seed clouds.

Molecules released by trees can seed clouds, two experiments have revealed. The findings, published on 25 May in Nature1, 2 and Science3, run contrary to an assumption that the pollutant sulphuric acid is required for a certain type of cloud formation — and suggest that climate predictions may have underestimated the role that clouds had in shaping the pre-industrial climate.

If the results of the experiments hold up, predictions of future climate change should take them into account, says Reto Knutti, a climate modeller at the Swiss Federal Institute of Technology (ETH Zurich). For 20 or more years, clouds have been the largest source of uncertainty in understanding how manmade emissions affect the atmosphere, he says.

In addition to releasing carbon dioxide, burning fossil fuels indirectly produces sulphuric acid, which is known to seed clouds. So, climate scientists have assumed that since pre-industrial times, there has been a large increase in cloud cover, which is thought to have an overall cooling effect by reflecting sunlight back into space. And they have assumed that this overall cooling effect has partially masked the climate’s underlying sensitivity to rising carbon dioxide levels. The latest experiments suggest that it may have been cloudier in pre-industrial times than previously thought.

If this is so, then the masking effect, and in turn the warming effects of carbon dioxide, might have been overestimated, says Jasper Kirkby, a physicist at the CERN, Europe’s particle-physics laboratory near Geneva, Switzerland, who led one of the experiments.