Do we need to be preparing for Arctic cruising strategies because of Global Cooling

[StuM]

Originally Posted by SailOar

Will you also predict that 2026 will be cooler than 2016, and that, in turn, 2036 will be cooler than 2026? If not, than your prediction is irrelevant; and if so, it will be wrong.

That's a very bold prediction. ON what basis do you make it?

[jackdale]

Originally Posted by StuM

Based on those cycles and the direction that solar activity seems to be going, I'll stick my neck out and say that slight cooling over the following 20-30 years is more likely than not, despite rising CO2 levels. This could well be followed by another warming cycle.

"That's a very bold prediction. ON what basis do you make it?"

The solar science community begs to differ.

The sun may provide the earth with most of its energy. The solar constant is pretty constant, it varies about 0.1%. The sun has little to do with climate change.

From the Stanford Solar Center:

During the initial discovery period of global climate change, the magnitude of the influence of the Sun on Earth's climate was not well understood. Since the early 1990s, however, extensive research was put into determining what role, if any, the Sun has in global warming or climate change.

A recent review paper, put together by both solar and climate scientists, details these studies: Solar Influences on Climate. Their bottom line: though the Sun may play some small role, "it is nevertheless much smaller than the estimated radiative forcing due to anthropogenic changes." That is, human activities are the primary factor in global climate change.

++++++++++++++++++

So a 40% increase in CO2 levels makes no difference, but a 0.1% variation in solar activity does.

[StuM]

Originally Posted by jackdale

The sun may provide the earth with most of its energy. The solar constant is pretty constant, it varies about 0.1%. The sun has little to do with climate change.

That would possibly be true if TSI was the only solar factor affecting climate.

[SailOar]

Originally Posted by StuM

That's a very bold prediction. ON what basis do you make it?

This brings us back to that 97% vs 3% discussion.

[SailOar]

Northern invaders threaten Antarctic marine life | Science Daily

The Antarctic Polar Front, a strong ocean front formed where cold Antarctic water meets warmer waters to the north, has historically been seen as a barrier preventing movement of marine life.

But the study has found the Antarctic Polar Front is often crossed by floating kelp that can form rafts carrying crustaceans, worms, snails and other seaweeds across hundreds of kilometres of open ocean.

"So far, the northern species don't seem to be surviving long in the cold, icy Antarctic. But with climate change and warming oceans, many non-Antarctic species could soon colonise the region," said lead researcher Dr Ceridwen Fraser, from the ANU Fenner School of Environment and Society.[...]

The research has been published in the journal Ecography.

[SailOar]

Climate Change is Tipping Scales Toward More Wildfires | Climate Central

The 2016 wildfire season has barely begun and dozens of large wildfires have already raged through Western states, with hundreds of thousands of acres burned. This comes on the heels of a 2015 wildfire season that was the worst on record in the U.S., with more than 10 million acres burned.

These are not just random events. Climate change is producing conditions ripe for wildfires, tipping the scales in favor of the dramatic increases in large wildfires we have seen across the West since the 1970s. Snowpack is melting earlier as winter and spring temperatures rise, and in most states an increasing percentage of winter precipitation is falling as rain, meaning there is often less snowpack to begin with. Summer temperatures are rising, particularly in Southwestern states, where the number of extremely hot days is steadily increasing, creating more days where forests and grasslands are dried out and ready to burn.[...]

• Across the Western U.S., the average annual number of large fires (larger than 1,000 acres) burning each year has more than tripled between the 1970s and the 2010s.
• The area burned by these fires has shown an even larger increase: in an average year, more than six times as many acres across the West were burned in the 2010s than in the 1970s.
• The fire season is 105 days longer than it was in the 1970, and is approaching the point where the notion of a fire season will be made obsolete by the reality of year-round wildfires across the West.

The situation in some individual states is more extreme:

• The average number of large fires burning each year on Forest Service land has increased at least 10-fold in the Northern Rocky Mountain states of Wyoming, Idaho, and Montana.
• In the Pacific Northwest, there are now five times as many large fires burning in a typical year in Washington as there were in the 1970s; in Oregon there are nearly seven times as many.[...]

[SailOar]

ExxonMobil Backs Carbon Tax For Climate Change | NASDAQ.com

ExxonMobil (XOM) is one of the top targets of environmental activists, pursued because of its alleged misinformation campaign on climate change over the past few decades. It may come as a surprise to many then that ExxonMobil is actually pressing U.S. legislators to pass a carbon tax in the name of addressing climate change.

The Wall Street Journal reports that ExxonMobil has quietly been lobbying members of the U.S. Congress to implement a carbon tax, essentially viewing it as one of the least bad options to curb greenhouse gas emissions. The thinking inside the oil supermajor is that it can no longer be seen as opposed to all climate action. Complete intransigence could risk less desirable outcomes for the oil industry, such as more restrictive regulations on oil and gas production. A carbon tax is a more efficient way to deal with greenhouse gas emissions, both Exxon and independent economists argue.

“Of the policy options being considered by governments, we believe a revenue-neutral carbon tax is the best,” Suzanne McCarron, Exxon’s vice president of public and government affairs, wrote in the Dallas Morning News in May.[...]

The support for a carbon tax stands in contrast to the Republican-led House of Representatives, which voted to condemn a carbon tax earlier this month.

The Wall Street Journal article comes a day after Politico reported that the American Petroleum Institute, a U.S.-based oil and gas trade group, is revamping its climate change strategy, an acknowledgement that the industry is increasingly on the back foot when it comes to the climate debate.[...]

[SailOar]

International Cryosphere Climate Initiative

Thresholds

Policy makers and the general public alike now largely accept that the Arctic, Antarctica and many mountain regions already have warmed two-three times faster than the rest of the planet. What is less understood, outside the scientific community, is that the very nature of the cryosphere – regions of snow and ice – carries dynamics that once triggered, in some cases cannot be reversed, even with a return to lower temperatures or CO2 levels. “Thresholds and Closing Windows: Risks of Irreversible Climate Change,” seeks to convey a message from IPCC AR5 and key cryosphere research since then: that at current commitment levels or INDCs, humanity faces very high risk of crossing certain irreversible thresholds in its cryosphere regions – setting into motion changes that cannot be stopped or reversed, in some cases not without a new “Little Ice Age”, and perhaps not even then. The only way to prevent these dynamics from beginning is to make sure temperatures never rise that high.

Read the report here (PDF)[...]

^^^^^^^^^^^^^^^^^^^^^^^

Thresholds and Closing Windows
Risks of Irreversible Cryosphere Climate Change

[from the SUMMARY]

[jackdale]

Originally Posted by Reefmagnet

Using the 2.13 constant, atmospheric CO2 content increased by 25.347 Gigatonnes. Based on this anthropogenic emissions must have been in the vicinity of 2.5 Gigatonnes, I guess, which seems to be in the ball bark especially if one considers that emissions wouldn't have started to ramp up until around 1850.

Did you miss this

That is total of about 15 billions of CO2 that has accumulated from 1750 to 1875.

[jackdale]

Originally Posted by StuM

That would possibly be true if TSI was the only solar factor affecting climate.

And to what only solar factors do you refer, that were not included on the graph?

[StuM]

Originally Posted by jackdale

And to what only solar factors do you refer, that were not included on the graph?

The scale on the axis of that graph was only TSI. The other factors shown varied by a lot than more your stated 0.1%.

Sun Spot Observations: range = 0 - 180
10.7 Flux: range = 60 - 240
Solar Flare Index: range = -40 to +40.

A few other factors not included:
UV emissions
EUV emissions
Solar magnetic field strength.
Solar wind variations
...

[jackdale]

Originally Posted by StuM

The scale on the axis of that graph was only TSI. The other factors shown varied by a lot than more your stated 0.1%.

Sun Spot Observations: range = 0 - 180
10.7 Flux: range = 60 - 240
Solar Flare Index: range = -40 to +40.

A few of other factors not included:
UV emissions
EUV emissions
Solar magnetic field strength.
Solar wind variations
...

OK - now let us see the correlations and mechanisms

[Reefmagnet]

Originally Posted by jackdale

Did you miss this

With unspecified units, I ignored it. But in the context of the author's discussion I think you'll find he's referring actual (blue) and anthropogenic (pink) increase to the initial baseline of 276.8 ppmv. To me, this means he's saying atmospheric co2 content increased by a factor of 10 compared to the value it would have if it were just anthropogenic contribution.

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[jackdale]

Originally Posted by Reefmagnet

With unspecified units, I ignored it. But in the context of the author's discussion I think you'll find he's referring actual (blue) and anthropogenic (pink) increase to the initial baseline of 276.8 ppmv. To me, this means he's saying atmospheric co2 content increased by a factor of 10 compared to the value it would have if it were just anthropogenic contribution.

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Sorry

Fixed

That is total of about 15 billion tonnes of CO2 that has accumulated from 1750 to 1875.

That would 15 / 2.13 = 7.0 additional ppm

277 + 7.0 = 284 ppm. His figure 2 shows 278.

His figure 1 bears little resemblance to the Law Dome graph from CDIAC.

[Reefmagnet]

Originally Posted by jackdale

Sorry

Fixed

That is total of about 15 billion tonnes of CO2 that has accumulated from 1750 to 1875.

His figure 1 bears little resemblance to the Law Dome graph from CDIAC.

I'm assuming the reason it doesn't resemble that graph is because the author used something more modern than a Commodore 64 to produce his graph.

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