Showing posts with label NASA. Show all posts
Showing posts with label NASA. Show all posts

Sunday, March 13, 2016

February Temperature


The February 2016 land and ocean temperature anomaly was 1.35°C (2.43°F) above the average temperature in the period from 1951 to 1980, as above image shows (Robinson projection).

On land, it was 1.68°C (3.02°F) warmer in February 2016, compared to 1951-1980, as the image below shows (polar projection).


The image below combines the above two figures in two graphs, showing temperature anomalies over the past two decades.


Below are the full graphs for both the land-ocean data and the land-only data. Anomalies on land during the period 1890-1910 were 0.61°C lower compared to the period from 1951 to 1980, which is used as a reference to calculate anomalies. The blue line shows land-ocean data, while the red line shows data from stations on land only.


At the Paris Agreement, nations committed to strengthen the global response to the threat of climate change by holding the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels.

To see how much temperatures have risen compared to pre-industrial levels, a comparison with the period 1951-1980 does not give the full picture. The image below compares the February 2016 temperatures with the period from 1890 to 1910, again for land only.


Since temperatures had already risen by ~0.3°C (0.54°F) before 1900, the total temperature rise on land in February 2016 thus is 2.6°C (4.68°F) compared to the start of the industrial revolution.

There are a number of elements that determine how much the total temperature rise on land will be, say, a decade from now:

Rise 1900-2016: In February 2016, it was 2.3°C (4.14°F) warmer on land than it was in 1890-1910.

Rise before 1900: Before 1900, temperature had already risen by ~0.3°C (0.54°F), as Dr. Michael Mann points out (see earlier post).

Rise 2016-2026: If levels of carbon dioxide and further greenhouse gases do keep rising, there will additional warming over the next ten years. Even with dramatic cuts in carbon dioxide emissions, temperatures can keep rising, as maximum warming occurs about one decade after a carbon dioxide emission, so the full wrath of the carbon dioxide emissions over the past ten years is still to come. Moreover, mean global carbon dioxide grew by 3.09 ppm in 2015, more than in any year since the record started in 1959, prompting an earlier post to add a polynomial trendline that points at a growth of 5 ppm by 2026 (a decade from now). This growth took place while global energy-related CO2 emissions have hardly grown over the past few years, indicating that land and oceans cannot be regarded as a sink, but should be regarded as source of carbon dioxide. On land, carbon dioxide may be released due to land changes, changes in agriculture, deforestation and extreme weather causing droughts, wildfires, desertification, erosion and other forms of soil degradation. Importantly, this points at the danger that such emissions will continue to grow as temperatures keep rising. New studies on permafrost melt (such as this one and this one) show that emissions and temperatures can rise much faster in the Arctic than previously thought. Furthermore, a 2007 study found a 25% soil moisture reduction to result in 2°C warming. Altogether, the rise over the next decade due to such emissions may be 0.2°C or 0.36°F (low) to 0.5°C or 0.9°F (high).

Removal of aerosols: With the necessary dramatic cuts in emissions, there will also be a dramatic fall in aerosols that currently mask the full warming of greenhouse gases. From 1850 to 2010, anthropogenic aerosols brought about a decrease of ∼2.53 K, says a recent paper. In addition, more aerosols are likely to be emitted now than in 2010, so the current masking effect of aerosols may be even higher. Stopping aerosol release may raise temperatures by 0.4°C or 0.72°F (low) to 2.5°C or 4.5°F (high) over the next decade, and when stopped abruptly this may happen in a matter of weeks.

Albedo change: Warming due to Arctic snow and ice loss may well exceed 2 W per square meter, i.e. it could more than double the net warming now caused by all emissions by people of the world, as Professor Peter Wadhams calculated in 2012. The temperature rise over the next decade due to albedo changes as a result of permafrost and sea ice decline may be 0.2°C or 0.36°F (low) to 1.6°C or 2.9°F (high).

Methane eruptions from the seafloor: ". . . we consider release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time," Dr. Natalia Shakhova et al. wrote in a paper presented at EGU General Assembly 2008. Authors found that such a release would cause 1.3°C warming by 2100. Such warming from an extra 50 Gt of methane seems conservative when considering that there now is only some 5 Gt of methane in the atmosphere, and over a period of ten years this 5 Gt is already responsible for more warming than all the carbon dioxide emitted by people since the start of the industrial revolution. The temperature rise could be higher, especially in case of large abrupt release, but in case of small and gradual releases much of the methane may be broken down over the years. The temperature rise due to seafloor methane over the next decade may be 0.2°C or 0.36°F (low) to 1.1°C or 2°F (high).

Water vapor feedback:
 "Water vapour feedback acting alone approximately doubles the warming from what it would be for fixed water vapour. Furthermore, water vapour feedback acts to amplify other feedbacks in models, such as cloud feedback and ice albedo feedback. If cloud feedback is strongly positive, the water vapour feedback can lead to 3.5 times as much warming as would be the case if water vapour concentration were held fixed", according to the IPCC. In line with the above elements, this may result in a temperature rise over the next decade of 0.2°C or 0.36°F (low) to 2.1°C or 3.8°F (high).

The image below puts all these elements together in two scenarios, one with a relatively low temperature rise of 3.9°C (7.02°F) and another one with a relatively high temperature rise of 10.4°C (18.72°F).


Note that the above scenarios assume that no geoengineering will take place.

The 2.3°C warming used in above image isn't the highest figure offered by the NASA site. An even higher figure of 2.51°C warming can be obtained by selecting a 250 km smoothing radius for the on land data.

When adding the 0.3°C that temperatures rose before 1900, the rise from the start of the industrial revolution is 2.81°C (5.06°F), as illustrated by the image on the right.

The image also shows that this is the average rise. At specific locations, it is as much as 16.6°C (30°F) warmer than at the start of the industrial revolution.

Furthermore, temperatures are higher on the Northern Hemisphere than on the Southern Hemisphere. This is illustrated by the image below showing NASA temperature anomalies for January 2016 (black) and February 2016 (red) on land on the Northern Hemisphere. The data show that it was 2.36°C (4.25°F) warmer in February 2016 compared to 1951-1980.


How much of the rise can be attributed to El Niño? The added trendlines constitute one way to handle variability such as caused by El Niño and La Niña events and they can also indicate how much warming could be expected to eventuate over the years to come.

The February trendline also indicates that the temperature was 0.5°C lower in 1900 than in 1951-1980, so the total rise from 1900 to February 2016 is 2.86°C (5.15°F). Together with a 0.3°C rise before 1900, this adds up to a rise on land on the Northern Hemisphere of 3.16°C (5.69°F) from pre-industrial levels to February 2016. Most people on Earth live on land on the Northern Hemisphere. In other words, most people are already exposed to a temperature rise that is well above any guardrails that nations at the Paris Agreement pledged would not be crossed.


Temperatures may actually rise even more rapidly than these trendlines indicate. As above image illustrates, the largest temperature rises are taking place in the Arctic, resulting in a rapid decline of snow and ice cover and increasing danger that large methane eruptions from the seafloor will take place, as illustrated by the image on the right, from an earlier post. This could then further lead to more water vapor, while the resulting temperature rises also threaten to cause more droughts, heatwaves and wildfires that will cause further emissions, as well as shortages of food and fresh water supply in many areas.

Adding the various elements as discussed above indicates that most people may well be hit by a temperature rise of 4.46°C or 8.03°F in a low rise scenario and of 10.96°C or 19.73°F in a high rise scenario, and that would be in one decade from February 2016. Since it is now already March 2016, that is less than ten years from now.

The image below shows highest mean methane readings on one day, i.e. March 10, over four years, i.e. 2013, 2014, 2015 and 2016, at selected altitudes in mb (millibar). The comparison confirms that the increase of methane in the atmosphere is more profound at higher altitudes, as discussed in earlier posts. This could indicate that methane from the Arctic Ocean is hardly detected at lower altitudes, as it rises in plumes (i.e. very concentrated), while it will then spread and accumulate at higher altitudes and at lower latitudes.


The conversion table below shows the altitude equivalents in mb, feet and m.

57016 feet44690 feet36850 feet30570 feet25544 feet19820 feet14385 feet 8368 feet1916 feet
17378 m13621 m11232 m 9318 m 7786 m 6041 m 4384 m 2551 m 584 m
 74 mb 147 mb 218 mb 293 mb 367 mb 469 mb 586 mb 742 mb 945 mb

Meanwhile Arctic sea ice area remains at a record low for the time of the year, as illustrated by the image below.


Next to rising surface temperatures in the Arctic, ocean temperature rises on the Northern Hemisphere also contribute strongly to both Arctic sea ice decline and methane releases from the seafloor of the Arctic Ocean, so it's important to get an idea how much the Northern Hemisphere ocean temperature can be expected to rise over the next decade. The NOAA image below shows a linear trend over the past three decades that is rising by 0.19°C per decade.

The image below, using the same data, shows a polynomial trend pointing at a 1.5°C rise in ocean temperature on the Northern Hemisphere over the next decade.


Below is another version of above graph.


The situation is dire and calls for comprehensive and effective action, as described in the Climate Plan.



Monday, January 19, 2015

Temperature Rise

Record High Temperatures in 2014

The year 2014 was the warmest year across global land and ocean surfaces since records began in 1880, writes NOAA, adding the graph below. This graph illustrates that temperatures have risen even when focusing on a relatively short recent period with a linear trendline starting in 1998, which was an El Niño year, whereas 2014 wasn't.

Source: NOAA Global Analysis - Annual 2014
Most Appropriate Trendline

While the purple 1998-2014 trendline serves the useful purpose of dispelling the myth that warming had halted recently, it isn't the most appropriate trendline, since extending this trendline backward to 1880 would leave too many data too remote from the trendline, as is further illustrated by the animated image below.


What about the blue linear trendline that is based on data for all the years from 1880 to 2014? By that same logic, the appropriateness of this trendline must also be questioned. Temperatures in recent years have been well above this trendline. A polynomial trendline seems a much better fit, as illustrated by the image below.


Above image also extends the trendline forward, showing that 2 degrees Celsius warming looks set to be exceeded in 2038, based on the same data.

And while this is a frightening scenario, the picture may well be much too optimistic, because the heat is felt most in the Arctic Ocean, the very location where some of the most terrifying feedbacks are accelerating local warming, as further explained below.

Feedbacks in the Arctic

As NOAA writes, much of the record warmth for the globe can be attributed to record warmth in the global oceans, which reached the highest temperature among all years in the 1880–2014 record.


As above image shows, ocean heat reached a record high in 2014. In other words, it was ocean heat that pushed the combined ocean and land temperature to a record high. Anomalies were especially high in the Arctic Ocean, as illustrated by the image below.


Waters close to Svalbard reached temperatures as high as 63.5°F (17.5°C) on September 1, 2014 (green circle). Note that the image below shows sea surface temperatures only. At greater depths (say about 300 m), the Gulf Stream is pushing even warmer water through the Greenland Sea than temperatures at the sea surface.


Since the passage west of Svalbard is rather shallow, a lot of this very warm water comes to the surface at that spot, resulting in an anomaly of 11.9°C. The high sea surface temperatures west of Svalbard thus show that the Gulf Stream can carry very warm water (warmer than 17°C) at greater depths and is pushing this underneath the sea ice north of Svalbard.


Planetary energy imbalance (0.6 W/m2) equals the amount of energy in exploding 400,000 Hiroshima atomic bombs per day, 365 days/year (J. Hansen, 16 Jan. 2015).



Planetary imbalance now is 0.6 W/m2. This has made the rise in ocean heat (up to 2000 m deep) more than double over the past decade. Data from 2005 through to 2014 contain a polynomial trendline that points at a similar rise by 2017, followed by an even steeper rise.

What could cause such non-linear rise?

The answer is feedbacks. Arctic snow and ice loss alone may well cause over 2 W/m2 warming, warns Prof. Peter Wadhams. Another such feedback is methane erupting from the ocean floor, as methane hydrates get destabilized due to higher temperatures.

As illustrated by the graph below, most of this excess heat is absorbed by oceans and ice. Some of the heat is consumed by the process of melting ice into water, and 93.4% of this excess heat ends up warming up the oceans.

Graph by Sceptical Science based on study by by Nuccitelli et al.
As the Gulf Stream keeps carrying ever warmer water into the Arctic Ocean, methane gets released in large quantities, as illustrated in the images below showing high methane levels over the East Siberian Arctic Shelf (red oval left) and over Baffin Bay (red oval right) with concentrations as high as 2619 ppb.

click on image to enlarge
The images below show methane levels on Jan 25 (top), and Jan 26, 2015 (bottom).



The threat is that huge amounts of methane will erupt from the seafloor of the Arctic Ocean over the coming decades, as illustrated by the image below.

For more on this image, see this post and this page.
Demise of the Arctic sea ice and snow cover is another terrifying feedback. The image below features a NASA/Goddard Space Flight Center Scientific Visualization Studio screenshot showing decline of multi-year Arctic sea ice area over the years.


Below is a video by Nick Breeze who interviews Professor Peter Wadhams on multi-year Arctic sea ice.


An exponential trendline based on sea ice volume observations shows that sea ice looks set to disappear in 2019, while disappearance in 2015 is within the margins of a 5% confidence interval, reflecting natural variability. In other words, extreme weather events could cause Arctic sea ice to collapse as early as 2015, with the resulting albedo changes further contributing to the acceleration of warming in the Arctic and causing further methane eruptions from the seafloor of the Arctic Ocean.

click on image to enlarge
As the Arctic continues to warm, the temperature difference between the equator and the Arctic declines, resulting in changes to the jet streams and polar vortex.

One such change is a slowing down of the speed at which the jet streams and polar vortex circumnavigate the globe, as discussed in a recent post.

The image on the right shows that the jet streams on the Northern Hemisphere reached speeds as high as 410 km/h (255 miles per hour) on January 9, 2015. Also note the jet stream crossing the Arctic Ocean, rather than staying between 50 and 60 degrees latitude, where the polar jet streams used to be.

The image below shows winds on January 11, 2015, at several altitudes, i.e. at 10 hPa | ~26,500 m (16.5 mile), high in stratosphere, polar vortex (left, at 250 hPa | ~10,500 m (6.5 mile), jet stream (center), and at 700 hPa | ~3,500 m (2.2 mile), high in planetary boundary layer.

click on image to enlarge
As a result, extreme weather events such as heatwaves and storms can be expected to occur with greater frequency and intensity, as also discussed in a recent post. Heatwaves can heat up the water in the North Atlantic, as it flows into the Arctic Ocean, driven by the Gulf Stream, while heatwaves can also warm up the water in rivers that end up in the Arctic Ocean. Heatwaves can also hit the sea ice in the Arctic Ocean directly, causing rapid sea ice melting, while storms can make the ice break up and be driven out of the Arctic ocean,

Demise of the sea ice and snow cover in the Arctic results in further acceleration of warming, not only due to less sunlight getting reflected back into space, but also due to loss of the buffer that currently absorbs huge amounts of heat as it melts in summer. With the demise of this latent heat buffer, more sunlight will instead go into heating up the water of the Arctic Ocean. For more on the latter, see the page on latent heat.


Above image illustrates some of the self-reinforcing feedback loops that have been highlighted in this and earlier posts. Further feedbacks are pictured in the image below.

from the Feedbacks page
Runaway Global Warming

Above feedbacks are already pushing the temperature rise in the Arctic through the 2°C guardrail.



Based on existing temperature data, global warming on land looks set to exceed 2°C (3.6°CF) warming by the year 2034, but methane eruptions from the seafloor of the Arctic Ocean could push up global temperature rise even faster, in a runaway global warming scenario.

click to enlarge image
This raises the specter of human extinction. With no action taken, there appears to be a 55% risk that humans will be extinct by the year 2045, while taking little action will only postpone near-term human extinction by a few years. Only with rapid implementation of comprehensive and effective action may we be able to avoid this fate.


Comprehensive and Effective Action

In conclusion, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog at climateplan.blogspot.com and as illustrated by the image below.






Saturday, April 6, 2013

How much will temperatures rise?

If we take the NASA Annual Mean Land-Ocean Temperatures and draw a projection into the future, temperatures will quickly be 3 degrees Celsius higher than the base period (1951-1980), i.e. well before 2050, as illustrated on image 1. below. 

Image 1. Temperatures will be 3 degrees Celsius higher well before 2050

Above projection appears to be steeper than even the worst-case scenario pictured by the IPCC for years, such as on the image below.

Image 2. from IPCC 2001. Projections of globally averaged surface temperature 2000-2100 are shown for six SRES scenarios and IS92a using a model with average climate sensitivity. The grey region marked "several models all SRES envelope" shows the range of results from the full range of 35 SRES scenarios in addition to those from a range of models with different climate sensitivities. The temperature scale is departure from the 1990 value.
Could temperatures rise faster in future than what the IPCC anticipated in 2001? The answer must be yes! In 2007, the IPCC described that, even if greenhouse gas concentrations in the atmosphere were stabilized for 100 years at year 2000 values (B1), then we would still be committed to a further warming of 0.5°Celsius. This committed warming should not be confused with ‘unavoidable climate change’ over the next half century, which would be greater because forcing cannot be instantly stabilized. And of course, as it turned out, emissions have not been stabilized at 2000 values, but have in fact increased substantially.

As it turned out, the models used by the IPCC made all kinds of assumptions that didn't eventuate. But before deciding to instead settle for a relatively simple extrapolation of observed data, there are some issues that require a further look.  

As discussed in the earlier post Accelerated Arctic Warming, temperatures in the Arctic have been rising at a much faster pace than global temperatures, and if this accelerated rise continues, we can expect a 10 degrees Celsius rise in the Arctic before 2040, as illustrated by image 3. below.  

Image 3. Three kinds of warming - 2: Accelerated warming in the Arctic 
Such a temperature rise in the Arctic will undoubtedly lead to additional greenhouse gas emissions in the Arctic, of carbon dioxide, nitrous oxide and particularly methane, threatening to trigger runaway global warming. 

The image below, from the methane-hydrates blog, combines these three kinds of warming, showing global temperatures that soon catch up with accelerated Arctic warming, as heatwaves at high latitudes will cause wildfires, in particular in Siberia, where firestorms in peat-lands, tundras and forests could release huge amounts of emissions, including soot, much of which could settle on the Himalayan plateau, darkening the ice and snow and resulting in more local heat absorption. Rapid melt of glaciers will then cause flooding at first, followed by dramatic decreases in the flow of river water that up to a billion people now depend on for water supply and irrigation.

In other words, the situation looks much more dire than what most models make us believe; the more reason to adopt the climate plan that is also described at the post at the methane-hydrates blog.

Image 4. Three kinds of warming - 1, 2 and 3 


References

- IPCC (TAR) - Climate Change 2001: Synthesis Report

- IPCC (AR4) - Climate Change 2007: Working Group I: The Physical Science Basis

- Accelerated Arctic Warming

- Methane hydrates

Friday, March 22, 2013

Arctic Ice Breaks Up in Beaufort Sea


The NOAA image below gives an update on the temperature anomaly over Greenland, as earlier discussed in the post including Huge patches of warm air over the Arctic.



Below a NOAA animation showing a 30-day loop (up to March 19, 2013) of analyzed 200-hPa heights and anomalies. An eleven-day mean, centered on the date indicated in the title, of 200-hPa heights and anomalies from the NCEP Climate Data Assimilation System (CDAS), is shown for the first 25 days of the animation. 10-, 9-, 8-, 7-, and 6-day running means are shown for the last 5 days, respectively. Contour interval for heights is 120 m, anomalies are indicated by shading. Anomalies are departures from the 1979-95 daily base period means.


As discussed in earlier posts (see below), changes to the jet stream are making extreme weather events increasingly likely to occur, which spells bad news for the sea ice.

Thursday, January 17, 2013

Accelerated Arctic Warming

The more northern we look, the more Earth is warming, as shown by the NASA image below.

global temperature anomalies averaged from 2008 through 2012, NASA Goddard Institute for Space Studies
The interactive image below shows temperature anomalies for the different latitudional zones over time.

The Arctic (red line above) clearly shows the strongest warming over time, while accelerating in recent years. The best fit for this warming in the Arctic is a fourth order polynomial trendline, as added to the data on the image below.


This accelerated warming in the Arctic is threatening to destabilize the methane in the seabed and trigger runaway global warming within a decade. Effective action needs to be taken before it's too late!

Wednesday, September 19, 2012

NSIDC calls record 2012 low

This NASA satellite image shows how the Arctic sea ice extent, on Sept. 16, 2012, compares to the average
minimum extent over the past 30 years (in yellow). Credit: NASA/Goddard Scientific Visualization Studio.
Arctic sea ice cover likely melted to its minimum extent for the year on September 16, says the National Snow and Ice Data Center (NSIDC), adding the note that this number is preliminarychanging weather conditions could still push the ice extent lower.

Sea ice extent—defined by NSIDC as the total area covered by at least 15 percent of ice—fell to 3.41 million square kilometers (1.32 million square miles), now the lowest summer minimum extent in the 33-year satellite record.

NSIDC adds that this minimum is 49% below the 1979 to 2000 average, as illustrated by the table below.

Table 1. Previous minimum Arctic sea ice extents
 YEARMINIMUM ICE EXTENTDATE
IN MILLIONS OF SQUARE KILOMETERSIN MILLIONS OF SQUARE MILES
20074.171.61September 18
20084.591.77September 20
20095.131.98September 13
20104.631.79September 21
20114.331.67September 11
20123.411.32September 16
1979 to 2000 average6.702.59September 13
1979 to 2010 average6.142.37September 15

NSIDC adds that the six lowest seasonal minimum ice extents in the satellite record have all occurred in the last six years (2007 to 2012). In contrast to 2007, when climatic conditions (winds, clouds, air temperatures) favored summer ice loss, this year’s conditions were not as extreme. Summer temperatures across the Arctic were warmer than average, but cooler than in 2007. The most notable event was a very strong storm centered over the central Arctic Ocean in early August. It is likely that the primary reason for the large loss of ice this summer is that the ice cover has continued to thin and become more dominated by seasonal ice. This thinner ice was more prone to be broken up and melted by weather events, such as the strong low pressure system just mentioned. The storm sped up the loss of the thin ice that appears to have been already on the verge of melting completely.

NASA says that this year, a powerful cyclone formed off the coast of Alaska and moved on August 5 to the center of the Arctic Ocean, where it churned the weakened ice cover for several days. The storm cut off a large section of sea ice north of the Chukchi Sea and pushed it south to warmer waters that made it melt entirely. It also broke vast extensions of ice into smaller pieces more likely to melt.

“The storm definitely seems to have played a role in this year's unusually large retreat of the ice”, said Claire Parkinson, a climate scientist at NASA Goddard Space Flight Center, Greenbelt, Md. “But that exact same storm, had it occurred decades ago when the ice was thicker and more extensive, likely wouldn't have had as prominent an impact, because the ice wasn't as vulnerable then as it is now.”

In the press release, NSIDC lead scientist Ted Scambos said that thinning ice, along with early loss of snow, are rapidly warming the Arctic. “But a wider impact may come from the increased heat and moisture the warmer Arctic is adding to the climate system,” he said. “This will gradually affect climate in the areas where we live,” he added. “We have a less polar pole—and so there will be more variations and extremes.”

The image below, from Arctic Sea Ice Blog, shows Arctic sea ice observations (in red) against the backdrop of models used in IPCC AR4 (2007) for projection of sea ice up to the year 2100.


The image below, from NSIDC sea ice news, shows the observed September sea ice extent for 1952-2011 (black line) against a backdrop of projections used by IPCC AR4 (blue) as well as proposed for use in IPCC AR5 (red).

Note: The record low value for 2012 still has to be added on this image. Credit: NSIDC, Stroeve et al.
The image shows that the recently observed decline in sea ice extent is steeper than the CMIP3 models with a “business as usual” SRESA1B greenhouse gas emissions scenario (blue line), as used by the IPCC in AR4.

It is also steeper than the more recent CMIP5 models using a RCP 4.5 scenario (pink line) that are proposed to be used by the IPCC in AR5.

RCP 4.5 is a scenario in which the global temperature rise would would soon exceed 2 degrees Celsius. Since the Arctic experiences accelerated warming, such a scenario would clearly be catastrophic. Looking at sea ice volume, rather than extent, would show this even more clearly.

Below, a NOAA animation showing sea ice decline in 2012 and a NASA animation showing the Arctic cyclone.