Global warming discussion IV

[Trakar]

Trakar,
Quite right - alas the 'Deniers of Science' continue to pretend that climate sensitivity is low, and therefore nothing to worry about.

What does worry me, is that global temperatures were flat for about 30 years, in the 20th Century, due to particulates. Without that, the rise in temperature up to today would be even higher.
Barring a really major volcanic event, I don't see anything that could cause such a 'hiatus' for the rest of this century, so perhaps even your estimate is a bit low - oops!

LOL, more seriously, however, I fear that a bit myself but with the time and effort I've put into this area, I'm pretty comfortable with a short-term (several decade) sensitivity in the 3-3.5ºC range. I generally tend to be more worried about non-linear bumps and jumps where periods of incremental increases are interspersed with jags of state-change increases. These are what can be expected as issues like large regions of the oceans, surface soils and biologic systems transition to becoming even larger and more regular emission sources rather than providing their traditional roles as carbon sinks. But hopefully we can focus on one problem at a time. Let us focus on our emissions first, then we can worry about restoring the mess that's left to a more sustainable configuration.

 

[lomiller]

On climate sensitivity.
It looks like global temperatures this year will reach, or even exceed, 1°C above pre-industrial global temperatures. This with only a ~43% increase of CO².

(400ppm - 280ppm = 120ppm, which is 120/280 * 100 = 42.857%)

So, with a 1°C increase in global temperatures for ~43% increase in CO², that would give a climate sensitivity of

100/43 = 2.3 * 1°C = 2.3°C

Now, I know this is a very simple and un-nuanced approach, but I think this does give a reasonable ballpark estimate of climate sensitivity.
What do you think?

BTW, Please feel free to correct any misconceptions or errors I may have committed

There are multiple issues, some of which cancel allowing you to get close to the generally accepted result.
The response to C02 is logarithmic not linear. So while doubling should yield a ~3 deg C temperature rise a 50% increase doesn’t mean a 1.5 deg C temperature rise. (it would actually be closer to 2)

It takes 2-3 decades for an increase in CO2 or any other forcing to be fully reflected in global temperatures due to the stabilizing influence of the oceans. Basically you need to warm up a really large amount of water before temperatures stabilize, and the energy that takes is ridiculously large. 2 W/m^2 over the entire surface of the atmosphere is a lot of energy each year, but still much smaller than the heat needs to build up in the Earth’s oceans before temperatures can climb. (1990 CO2 levels may work better for an approximation)

There is also a significant amount of global dimming that needs to be accounted for. In addition to CO2 humans also emit large amounts of aerosols that cool the planet. The 1 degree warming the earth has seen so far has been in spite of nearly 1 degree C worth of cooling due to these aerosols. Aerosols have a very strong but relatively short lived cooling impact. A new coal power plant, for example, actually cools the earth for the first 20 years of operation due to its aerosol emissions. It’s approximately 10 before atmospheric aerosol stop rising due to its emissions and another 10 before the continued CO2 emissions catch up to the cooling from the aerosols. If the plant shut down the cooling from its aerosol emissions would dissipate in 5-10 years creating a pulse of warming.

The last is one of the dangers of not acting soon enough. We could paint ourselves into a corner where cutting CO2 emissions would also cut aerosol emissions to the point where we are rapidly pushed over the danger threshold. A slow steady reduction in the use of fossil fuels is better, but that depends on us starting sooner.

 

[Belz...]

Why do I always read your username as "lolmiller"?

The last is one of the dangers of not acting soon enough. We could paint ourselves into a corner where cutting CO2 emissions would also cut aerosol emissions to the point where we are rapidly pushed over the danger threshold. A slow steady reduction in the use of fossil fuels is better, but that depends on us starting sooner.

Damn. I did not know that. It's almost as if knowing stuff about science is important to understanding AGW.

 

[macdoc]

I generally tend to be more worried about non-linear bumps and jumps where periods of incremental increases are interspersed with jags of state-change increases.

Very hard on stressed biomes like coral reefs where one bad year can do a lot of damage.

Also consider that 1 degree C globally translates to 2-3 C in the northern part of the world.
Canadian winters are up 3.2 C over 60 years....so those global averages are very misleading.
The tropic bands are already expanding northward and to the south by about 200 km each direction and as we've seen in Australia recently ....there can be a sudden shift of ocean populations as warming waters allow expansion of subtropic and even tropic fish.

England in particular has seen huge shifts ....some species moving north by 700 KM.

 

[Reality Check]

Haig: Your question about Salby's denial of climate science has been answered

We are NOT talking about me we are talking about Dr. Murry Salby and his science.

Demands to debunk the invalid science of a climate change denier from another climate change denier will be ignored, Haig, especially when the claims have already been debunked !
Haig's 25 parroted ignorance and lies from climate change deniers dating from 11 May 2015 with the list continuing to grow !

1. 26 November 2015 Haig: Still does not know that YouTube videos are not scientific literature and that personal opinions are not science!
2. 26 November 2015 Haig: Ignorant enough about climate science to link to Murry Salby denying climate science.
3. 26 November 2015 Haig: Repeats his ignorance that YouTube videos are not scientific literature and that personal opinions are not science!
4. 26 November 2015 Haig: Salby lies about climate sensitivity being below 0.2C by cherry picking unnamed studies.
5. 26 November 2015 Haig: Salby reveals his ignorance about the implications of low climate sensitivity.
6. 26 November 2015 Haig: Salby is in denial of valid climate science that has multiple lines of evidence that our CO2 emissions are increasing CO2 levels in the atmosphere.
7. 26 November 2015 Haig: Salby may be so in denial of AGW that he is willing to deny the greenhouse effect!

There is a really insane tactic of deniers of science such as creationists that you seem to be determined to follow, Haig. They ask questions of one person, ignore the answers, ask another person the same questions, ignore the answers, ask another person the same questions, ignore the answers, etc.
27 November 2015 Haig: Your question about Salby's denial of climate science has been answered.

 

[Reality Check]

http://www.desmogblog.com/2013/07/1...niversity--banned-national-science-foundation.

A note on that article - the link to the NSF case for banning Salby from funding for 3 years is not directly to the PDF.
You end up at Search Case Closeout Memoranda and have to enter the case number which is I06090025. The closeout memo page 1 has

Our investigation determined that the subject:'

• submitted significantly overlapped proposals to NSF and another federal agency;
• received compensation from NSF awards substantially in excess of approved budget amounts;
• overcharged NSF awards for indirect costs on a subcontract, and failed to disclose the subcontract to NSF;
• received payments for effort that he documented with questionable time and effort reports;
• and failed to comply with his University's conflicts of interest and financial disclosure policy.

This was not just a case of a few bad timesheets. This was a period of 15 years of deceptive practices.

 

[Haig]

IIRC Haig has actually been predicting an imminent ice age for several years.

Not quite accurate Pixel42

I reported Dr. Sc. Habibullo Abdussamatov in his prediction of a Little Ice Age beginning about 2014 and Global Temperature falling sharply after the Maximum of Solar Cycle 25 has passed.

A little ways to go yet until the big drop but the Pause is in line with his forecast.

THE SUN DEFINES THE CLIMATE PDF

Habibullo Abdussamatov: Bicentennial Decrease of the Total Solar Irradiance Leads to Unbalanced Thermal Budget of the Earth and the Little Ice Age

 

[macdoc]

These have all been shown to be factually incorrect numerous times and repeating the claims is contrary to the mod note

Try some climate science instead of woo.

WMO: 2015 likely to be Warmest on Record, 2011-2015 Warmest Five Year Period
Press Release
N° 13
25 November 2015
Climate Change Breaches Symbolic Thresholds, Fuels Extreme Weather

Geneva 25 November 2015 (WMO) The global average surface temperature in 2015 is likely to be the warmest on record and to reach the symbolic and significant milestone of 1° Celsius above the pre-industrial era. This is due to a combination of a strong El Niño and human-induced global warming, according to the World Meteorological Organization (WMO).

The years 2011-2015 have been the warmest five-year period on record, with many extreme weather events - especially heatwaves - influenced by climate change, according to a WMO five-year analysis.

"The state of the global climate in 2015 will make history as for a number of reasons," said WMO Secretary-General Michel Jarraud. "Levels of greenhouse gases in the atmosphere reached new highs and in the Northern hemisphere spring 2015 the three-month global average concentration of CO2 crossed the 400 parts per million barrier for the first time. 2015 is likely to be the hottest year on record, with ocean surface temperatures at the highest level since measurements began. It is probable that the 1°C Celsius threshold will be crossed," said Mr Jarraud. "This is all bad news for the planet."

Greenhouse gas emissions, which are causing climate change, can be controlled. We have the knowledge and the tools to act. We have a choice. Future generations will not."

"Added to that, we are witnessing a powerful El Niño event, which is still gaining in strength. This is influencing weather patterns in many parts of the world and fuelled an exceptionally warm October. The overall warming impact of this El Niño is expected to continue into 2016," said Mr Jarraud.

WMO issued its provisional statement on the status of the climate in 2015, and an additional five-year analysis for 2011-2015, to inform negotiations at the U.N. Climate Change Conference in Paris.

A preliminary estimate based on data from January to October shows that the global average surface temperature for 2015 so far was around 0.73 °C above the 1961-1990 average of 14.0°C and approximately 1°C above the pre-industrial 1880-1899 period.

This temperature tendency indicates that 2015 will very likely be the warmest year on record. The global average sea-surface temperature, which set a record last year, is likely to equal or surpass that record in 2015. The global average temperatures over land areas only from January to October suggest that 2015 is also set to be one of the warmest years on record over land. South America is having its hottest year on record, as is Asia (similar to 2007), and Africa and Europe their second hottest.

According to preliminary figures as of the end of September 2015, 2011-15 was the world’s warmest five-year period on record, at about 0.57°C (1.01°F) above the average for the standard 1961-90 reference period.
It was the warmest five-year period on record for Asia, Europe, South America and Oceania, and for North America. WMO compiled the five-year analysis because it provides a longer-term climate signal than the annual report.

https://www.wmo.int/media/content/w...est-record-2011-2015-warmest-five-year-period

Atmosphere

igure 2: Global annual average temperatures anomalies (relative to 1961-1990) based on an average of three global temperature data sets (HadCRUT.4.4.0.0, GISTEMP and NOAAGlobalTemp) from 1950 to 2014. The 2015 average is based on data from January to October. Bars are coloured according to whether the year was classified as an El Niño year (red), a La Niña year (blue) or an ENSO-neutral year (grey).Note uncertainty ranges are not shown, but are around 0.1°C.

Ocean

Figure 4: Ocean heat content down to a depth of 700m (left) and 2000m (right). Three-month (red), annual (black) and 5-year (blue) averages are shown. Source: NOAA NCEI

Cryosphere

http://www.skepticalscience.com//pics/WGMS2014.png

Get over it...it's getting warmer, we're responsible. Move on.

 

[Reality Check]

Haig: Repeats a delusion that a Maunder Minimum will cause a Little Ice Age

I reported Dr. Sc. Habibullo Abdussamatov in his prediction of a Little Ice Age beginning about 2014 and Global Temperature falling sharply after the Maximum of Solar Cycle 25 has passed.

Haig, you have repeatedly reported Dr. Sc. Habibullo Abdussamatov real ignorance of climate science based on your denial of climate science !
Ignoring the facts that 2014 was the warmest year on record and 2015 is probably going to exceed 2014 is total denial, Haig.

Haig's 32 parroted ignorance and lies from climate change deniers dating from 11 May 2015 with the list continuing to grow!

1. 27 November 2015 Haig: Your question about Salby's denial of climate science has been answered.
2. 30 November 2015 Haig: Repeats a delusion that a Maunder Minimum will cause a Little Ice Age!
   5 years of repeating Abdussamatov's ignorance turns your denial into a delusion, Haig, because you know that the climate science is that a new Maunder Minimum will only reduce global warming .
   • 13th May 2010 Haig: Russian Scientist, Dr. Habibullo Abdussamatov, Got Global Warming Predictions Wrong!
   • 3rd July 2012 Haig: No because he is ignorant of the science that global warming has been disconnected from the Sun for over 30 years and that it is CO2 that is the primary driver of climate change now
   • 29th July 2014 Haig: Habibullo Abdussamatov's 2009 paper is very bad.
   • 12th May 2015 Haig: New Maunder Minimum = new Little Ice Age is a fantasy
   • 2 September 2015 Haig: Abdussamatov lied in 2009 about the Sun causing global warming.
   • 2 September 2015 Haig: Persisting in an ignorant parroting of the ignorance of Abdussamatov does not make his invalid science valid!
   • 9 September 2015 Haig: One more ignorant repeat of Abdussamatov's ignorance of climate science!

 

[Reality Check]

Haig: It is a lie that Abdussamatov's "forecast" matches temperature data

A little ways to go yet until the big drop but the Pause is in line with his forecast.

That happens to be a lie, Haig, on 3 counts.

1. There is no "Pause".
2. As you know Habibullo Abdussamatov has no forecast in his 2009 paper. A climate forecast needs climate science which Abdussamatov displays total ignorance about in that 2009 paper. The main failure is completely ignoring the Earth's atmosphere!
3. What Abdussamatov has is Figure 8 which looks like a hand drawn "forecast" that predicts no temperature change from 2008 up to about 2019 or 2020. But temperature have increased from 2008 to 2015 in all datasets (e.g. Wood for Trees for HADCRUT4).

30 November 2015 Haig: It is a lie that Abdussamatov's "forecast" matches temperature data from 2008 to 2015.

 

[macdoc]

This is the kind of risks that will increase and have increased already ...more intense storms that are double edged...

Southern Queensland storm chasers reflect on 'bittersweet' storms
Peter Gunders, Monday November 30, 2015 - 18:02 EDT

A regional photographer says weekend storms brought "awe inspiring" images, but his thoughts were with the farmers who experienced massive damage.

When Bobby Skidmore was driving towards Warwick to capture images of the weekend thunderstorms, he reflected on both the excitement and dread storms bring at this time of year.

"It's a double-edged sword," he said.

"The storms are great to look at, but by the time the storm is over and I am sitting at home, the farmers are left counting their losses and cleaning up big messes."

Wild storms struck melon crops on the Western Downs, .

"I see all the fields and the livestock and the large farm sheds filled with hay and feed, and I really feel for the farmers."

Mr Skidmore said he believed the storms this season had been more intense than this time last year.

"And it's not even summer yet," he said.

"We've still got a long way to go this season."

Images of the storm that hit Warwick show the telltale green tinged-clouds of hail.

"The clouds started to look really intimidating," Mr Skidmore said.

"It was the most intense green, and you just knew that stacked inside that storm was a big hail system."

In Warwick, fellow storm chaser Terry West was kilometres away, but could hear the same noise.

"It roared like a freight train," he said.

"These storms bring a lot of rain and we need it, but it is a catch 22.

"The high winds and the hail cost the farmers a lot of money."

http://www.weatherzone.com.au/news/...-chasers-reflect-on-bittersweet-storms/409846

The storms are feature of the season ....the intensity of them is increasing as is the lengthening of the season during which they occur ...welcome to the Holocene.

 

[Lennart Hyland]

Didnt IPCC state that neither the intensity nor the frequency of the storms would increase?

 

[Mikemcc]

Didnt IPCC state that neither the intensity nor the frequency of the storms would increase?

AR5 WG1 has a table (11.2) comparing the different studies into storm intensity and frequency. The general thrust is, as stated, little change to frequency, but an increase in intensity and precipitation. It is difficult to quantify it though, which is why they state the predictions are with low confidence.

http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter11_FINAL.pdf

 

[macdoc]

Didnt IPCC state that neither the intensity nor the frequency of the storms would increase?

You don't need to rely on prediction....the physical record is clear for increased intensity both in cyclonic storms and other types.
This intensity includes rain/snow amounts as well as windspeeds or could be both.

Atlantic hurricanes are a different story as they have wind sheer complications.
As the tropics expand and the subtropics as well - areas that are not normally subject to intense rain events are getting a month of rain in a day ....infrastructures are simply not up to dealing with that.

Toronto's cost was close to a billion dollars for a non-cyclonic storm event. a couple years ago

A year after the worst flash flood in the City of Toronto’s history, some homeowners’ insurance premiums are up 15 to 20 per cent, spending on basement flood protection equipment is rising, and Mother Nature remains as unpredictable as ever.
The July 8 storm that lashed the city, flooded basements, stranded Go Train passengers and destroyed a Toronto lawyer’s $192,000 Ferrari contributed to the worst year in history for insurance claims across Canada.
It wasn’t just insurers who felt the impact. The city has boosted spending on water and sewer improvements, while homeowners are spending more to try to prevent future backups
Insurers paid out nearly $1 billion to cover the cost of the Toronto flood, as much as they’d spent on weather-related damage across the entire country in each of the four previous years.

http://www.thestar.com/business/per...014/07/05/a_year_after_the_toronto_flood.html

A smaller community to the west also got slammed last year with 2 months of rain in a few hours

Burlington flood: 2 months worth of rain falls within hours ...
www.cbc.ca/.../burlington-flood-2-months-worth-of-rain-falls-within-ho...
Aug 5, 2014 - Much of southern Ontario was under severe thunderstorm warning, watches Monday afternoon. .

even a while back Bombay got hit with nearly a meter of rain in 24 hours ......off the charts compared to any preceding record.

Snow storms are expected to increase in intensity as well even tho snow cover is falling.
Boston got buried last year.

UK has finally started naming storms and have just simply been deluged with high wind intense rainfall and snow fall this year

Abigail, Britain's first named storm, in pictures - Telegraph
www.telegraph.co.uk › News › Weather
Storm Abigail, Britain's first named storm, is causing major disruption with power cuts and school closures as gale force winds batter the country. Gales in the

http://www.telegraph.co.uk/news/weather/11993710/Abigail-Britains-first-named-storm-in-pictures.html

Then a second slammed in on top of soaked ground.
The infrastructure costs and added insurance costs are unreal...there is too much focus on heat records etc.

Taiwan got hit with a Cat 2 Cyclone....nothing special in wind speed but it dumped a year of rain in 2 days and this year there were 5 Super typhoons

he most powerful storm of 2015 is on a collision course with Japan and Taiwan. With winds of over 350kmh, Typhoon Soudelor has already wreaked havoc on a group of tiny islands in the Pacific Ocean. It is expected to make landfall sometime on Thursday.
The tropical storm ripped through the Northern Marianas on Sunday, which are some 2,500km due east of the Philippines. However, it hasn’t taken any lives yet. Winds have been gusting up to 354kmh (220mph

https://www.rt.com/news/311553-typhoon-pacific-japan-taiwan/

The insurance companies are very aware of the rising toll...

 

[Red Baron Farms]

Full-text advance copy of UNEP's "The Emissions Gap Report 2015"

As a general rule I don't like the focus on emissions only. That's only 1/2 the battle. But it is important none the less.

 

[Trakar]

Didnt IPCC state that neither the intensity nor the frequency of the storms would increase?

Yes; the type, frequency and intensity of extreme events are expected to change as Earth’s climate changes, and these changes could occur even with relatively small mean climate changes. Changes in some types of extreme events have already been observed, for example, increases in the frequency and intensity of heat waves and heavy precipitation events (see FAQ 3.3).

https://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-10-1.html 2007

From AR5 (2013) there is a bit more detail:
(http://www.climatechange2013.org/images/report/WG1AR5_ALL_FINAL.pdf -download link for .pdf of AR5)

Projected Changes in Extremes

In most land regions the frequency of warm days and warm
nights will likely increase in the next decades, while that of
cold days and cold nights will decrease...

The frequency and intensity of heavy precipitation events over
land will likely increase on average in the near term...

There is low confidence in basin-scale projections of changes
in the intensity and frequency of tropical cyclones (TCs) in all
basins to the mid-21st century...

Chapter 12 covering the longer term projections out to 2100 or so, is worth looking at as well.

 

[lomiller]

Didnt IPCC state that neither the intensity nor the frequency of the storms would increase?

I don’t recall what the IPCC report said, but the bulk of current literature suggests that hurricanes will become more intense but changes in frequency is uncertain due to increased wind shear which makes in more difficult for hurricanes to organize. I’m not sure if there is a statistically significant observable trend in storm size yet, but I believe there is some anecdotal evidence.

 

[Lennart Hyland]

Thank you Guys for clearing that up! I just noticed alot of the deniers use that IPCC predictions as a source for their claims when it comes to storms...

 

[macdoc]

significant observable trend in storm size yet,

There is but size is not intensity.

There is physical size ( Yazi for instance ...close to the size of the continental US )
Wind speed ( that little tight beast off Mexico recently)
Rain intensity ( even for not cyclonic storms ).

some snips

he United States is already experiencing more intense rain and snow storms.

As the Earth warms, the amount of rain or snow falling in the heaviest one percent of storms has risen nearly 20 percent on average in the United States—almost three times the rate of increase in total precipitation between 1958 and 2007.

In other words, the heaviest storms have very recently become even heavier.

The Northeast has seen a 74 percent increase in the amount of rain or snow falling in the heaviest storms.

http://www.ucsusa.org/global_warmin...warming-rain-snow-tornadoes.html#.Vl3fCzaS5Z8

good overview

The ACE index is calculated by adding each tropical storm, hurricane or typhoon's wind speed through its life cycle.

Long-lived, intense hurricanes have a high ACE index. Short-lived, weak tropical storms, a low ACE index. The ACE of a season is the sum of the ACE for each storm and takes into account the number, strength and duration of all the tropical storms in the season.

With typhoons Goni and Atsani in the Pacific now, this number will skyrocket.

(MORE: Twin Typhoons)

These ACE index values in the western North Pacific Ocean are more than two and a half times the year-to-date average, and exceeds those from all of 2014 (254), according to Dr. Ryan Maue, atmospheric scientist at WeatherBell, who tracks global ACE index values.


Enlarge
Tracks of all 2015 northwest Pacific named storms through August 21.
Seventeen storms, 12 of which reached typhoon (equivalent to hurricane) status, have flared up so far in 2015 in the northwest Pacific basin. This includes Typhoon Halola, which migrated westward from the central Pacific basin.

Six of the storms – Maysak, Noul, Dolphin, Nangka, Soudelor and Atsani – hit super typhoon status, with maximum estimated sustained winds topping 150 mph.

When adding the eastern North Pacific basin, Klotzbach said the 12 Category 4 or 5 tropical cyclones this year through Tuesday, Aug. 18, set a year-to-date record for the Northern Hemisphere, smashing the previous record of seven such intense tropical cyclones tied in 2014, according to records dating to 1971.

Klotzbach said the previous earliest date this occurred -- 12 Category 4 or 5 northern hemisphere tropical cyclones -- was on September 13. Incredibly, three-quarters of all Northern Hemisphere hurricanes or typhoons so far in 2015 have been at least Category 4 strength, according to Klotzbach.

This is impressive since the Atlantic basin had yet to produce a single hurricane, much less one of that intensity.

The Pacific tropical activity can be attributed, in part, to impressively warm ocean water.

"The high ACE values we've seen in the northeast and northwest Pacific basins are consistent with El Nino," Klotzbach said in early June.

El Nino is an anomalous, yet periodic, warming of the central and eastern equatorial Pacific Ocean. For reasons still not well understood, every 2 to 7 years, this patch of ocean warms for a period of 6 to 18 months.

(MORE: Strong El Nino Likely | Atlantic Season Outlook)

The eastern Pacific basin typically sees an increase in named storms during a moderate to strong El Nino thanks to diminished vertical wind shear.

The opposite is true in the Atlantic basin, since wind shear tends to increase in a moderate to strong El Nino, particularly in the Caribbean Sea.

http://www.weather.com/storms/typho...ific-tropical-cyclone-activity-record-aug2015

It's the mid latitude cities with non-cyclonic events that are getting taken by surprise - getting a month or more of rain in a matter of hours. ( or snow at times )

There is a plain commonsense aspect...a warmer atmosphere carries more water vapour - up 5% so far
A warmer ocean drives cyclonic storms which are heat engines.

El Nino just piles on top so the Pacific is incredibly hot this year.

In addition to this....cyclonic storms are showing up in unusual regions. Yemen for instance this year.

IPCC is not a science body but acts as a clearing house for the science and the policies and tends to be conservative.

Good news is despite global growth C02 growth was miniscule this year

Global carbon emissions growth slowed for third straight ...
arstechnica.com/.../2015/.../global-carbon-emissions-slowed-for-third-str...
by John Timmer - Nov 27, 2015 12:00pm PST ... percent, showing a partial decoupling between the growth in global CO2 emissions and that in the economy .

 

[Mikemcc]

In case anyone got taken in by Furcifer's BS, SkS have come up with a very good article about the impact of meat product on climate change:

http://www.skepticalscience.com/how-much-meat-contribute-to-gw.html#.Vl3pb3RbOPI.facebook