From Miami to Shanghai : 3C of warming will leave world cities below sea level

How Shanghai would look with a rise of just 2C: the UN warned this week of a potential 3C scenario.

Photograph: Nickolay Lamm/Courtesy Climate Central

From The Guardian by Jonathan Watts

An elevated level of climate change would lock in irreversible sea-level rises affecting hundreds of millions of people, Guardian data analysis shows

Hundreds of millions of urban dwellers around the world face their cities being inundated by rising seawaters if latest UN warnings that the world is on course for 3C of global warming come true, according to a Guardian data analysis.

Famous beaches, commercial districts and swaths of farmland will be threatened at this elevated level of climate change, which the UN warned this week is a very real prospect unless nations reduce their carbon emissions.

The Climate Science Special Report,

which was approved by the White House,

was compiled by US government scientists.

Data from the Climate Central group of scientists analysed by Guardian journalists shows that 3C of global warming would ultimately lock in irreversible sea-level rises of perhaps two metres.
Cities from Shanghai to Alexandria, and Rio to Osaka are among the worst affected.
Miami would be inundated - as would the entire bottom third of the US state of Florida.

The Guardian has found, however, that local preparations for a 3C world are as patchy as international efforts to prevent it from happening.
At six of the coastal regions most likely to be affected, government planners are only slowly coming to grips with the enormity of the task ahead - and in some cases have done nothing.

This comes ahead of the latest round of climate talks in Bonn next week, when negotiators will work on ways to monitor, fund and ratchet up national commitments to cut CO2 so that temperatures can rise on a safer path of between 1.5 and 2C, which is the goal of the Paris agreement reached in 2015.

The momentum for change is currently too slow, according to the UN Environment Programme.
In its annual emissions gap report, released on Tuesday, the international body said government commitments were only a third of what was needed.
Non-state actors such as cities, companies and citizens can only partly fill this void, which leaves warming on course to rise to 3C or beyond by the end of this century, the report said.

The UN’s environment chief, Erik Solheim, said progress in the year since the Paris agreement entered into force has been inadequate.
“We still find ourselves in a situation where we are not doing nearly enough to save hundreds of millions of people from a miserable future,” he said.

 South Beach, Miami, would be mostly underwater.

Photograph: Nickolay Lamm/Courtesy Climate Central

Nature’s ability to help may also be diminishing.
On Monday, the World Meteorological Organisation said concentrations of carbon dioxide in the atmosphere rose last year at a record speed to reach 403.3 parts per million - a level not seen since the Pliocene era three to five million years ago.

A 3C rise would lead to longer droughts, fiercer hurricanes and lock in sea-level rises that would redraw many coastlines.
Depending on the speed at which icecaps and glaciers melt, this could take decades or more than a century.
Colin Summerhayes of the Scott Polar Research Institute in Cambridge said three-degrees of warming would melt polar and glacier ice much further and faster than currently expected, potentially raising sea levels by two metres by 2100.

At least 275 million city dwellers live in vulnerable areas, the majority of them in Asian coastal megacities and industrial hubs such as Shanghai, Shenzhen, Bangkok and Tokyo.

Japan’s second biggest city, Osaka, is projected to lose its business and entertainments districts of Umeda and Namba unless global emissions are forced down or flood defences are built up.
Officials are reluctantly accepting they must now put more effort into the latter.

“In the past our response was focused on reducing the causes of global warming, but given that climate change is inevitable, according to the Intergovernmental Panel on Climate Change (IPCC), we are now discussing how to respond to the natural disasters that will follow,” said Toshikazu Nakaaki of the Osaka municipal government’s environment bureau.

two°C - New-York City from Maxime // Menilmonde

What if New-York City was underwater? Is this scenario possible?
All the explanations on this film are on menilmonde.com/two-c-new-york/ 

In Miami - which would be almost entirely below sea level even at 2C warming - the sense of urgency is evident at city hall, where commissioners are asking voters to approve a “Miami Forever” bond in the November ballot that includes $192m for upgrading pump stations, expanding drainage systems, elevating roads and building dykes.

Elsewhere, there is less money for adaptation and a weaker sense of urgency.
In Rio de Janeiro, a 3C rise would flood famous beaches such as Copacabana, the waterfront domestic airport, and many of the sites for last year’s Olympics.
But the cash-strapped city has been slow to prepare.
A report compiled for Brazil’s presidency found “situations in which climate changes are not considered within the scope of planning”.

Image of Candelária Church in Rio, Brazil, with a 4°C temperature rise scenario.

In Egypt, even a 0.5m sea-level rise is predicted to submerge beaches in Alexandria and displace 8 million people on the Nile Delta unless protective measures are taken, according to the IPCC.
But local activists say the authorities see it as a distant problem.
“As far as I’m concerned, this issue isn’t on the list of government priorities,” said Ahmed Hassan, of the Save Alexandria Initiative, a group that works to raise awareness of the effects of climate change on the city.

The impacts will also be felt on the economy and food production.
Among the most vulnerable areas in the UK is Lincolnshire, where swaths of agricultural land are likely to be lost to the sea.

“We’re conscious that climate change is happening and perhaps faster than expected so we are trying to mitigate and adapt to protect people and property.
We can’t stop it, but we can reduce the risk.” said Alison Baptiste, director of strategy and investment at the UK Environment Agency.
She said the measures in place should protect most communities in the near and medium term, but 50 years from now the situation will become more challenging.
“If climate change projections are accurate, we’re going to have to make some difficult decisions.”

Links :

• The Guardian : The three-degree world: the cities that will be drowned by global warming / UN warns of 'unacceptable' greenhouse gas emissions gap / Global atmospheric CO2 levels hit record high / Lincolnshire's coast and farms will sink with 3C of warming
• NYTimes : What the Climate Report Says About the Impact of Global Warming
• NPR : Massive Government Report Says Climate Is Warming And Humans Are The Cause
• Engadget : Federal report says humans are the cause of climate change 

Monitoring coastal zone changes from space

Sentinel-2A natural-color satellite image of the Sundarbans area in the Ganges-Brahmaputra Delta, captured on 18 March 2016.

The erosional forces from the sea and wind along the coast continuously change the landscape, together with the huge amount of silt and other sediments deposited in the countless estuaries, visible in the water.

Satellite images are a key component of coastal monitoring efforts, especially in rapidly changing areas such as this.

Credit: European Space Agency

From EOS by A. Cazenave, G. Le Cozannet, Jérôme Benveniste, P. L. Woodworth, and N. Champollion

The world’s coastal zones, currently home to a large fraction of the world’s population, are under serious threat from coastal erosion, cyclones, storms, and saltwater incursion into estuaries and coastal aquifers.
In the future, scientists expect these hazards to increase because of the combined effects of sea level rise, climate change, human activities, and population increase.

How coastal environments respond to natural and anthropogenic factors depends on the characteristics of the forcing agents, as well as on the properties of the coastal systems that remain poorly known and mostly unsurveyed on a global scale.
To better understand changes affecting coastal zones and to provide useful information to decision-makers, we need to collect and analyze various types of observations with global coverage.

In this context, observations from space represent an important complement to existing in situ observing systems (e.g., regional tide gauge networks).
Here we highlight the benefit of systematic coastal monitoring from space.
Such data combined with in situ observations and databases will be extremely useful to constrain models of coastal change.

The ruins of Fort Beauregard (also known as Fort Proctor) are partly submerged in Lake Borgne, east of New Orleans, La.

Many coastal areas are sinking even faster than sea level is rising.

Credit: Frank McMains

Issues with Coastal Monitoring

Regional sea level change, winds, waves, currents, extreme events, vertical ground motions, river runoff, sediment supply, land use change and urbanization, policies, and regulations all act as forcing agents on coastal zones.
Satellites have a tremendous potential to observe and characterize these forcing agents, but often, their instruments are not adapted to the special conditions of coastal zones.

For example, coastal residents are particularly concerned about rising sea levels in response to anthropogenic global warming.
High-precision satellite altimetry has considerably improved our understanding of sea level variations at global and regional scales, but that is not the case for coastal areas.
In terms of impacts, what counts at the coast is the sum of global mean rise, superimposed regional variability, small-scale ocean processes, and local vertical land motions.

Satellite altimetry, optimized for the open ocean, performs poorly within 10 kilometers of the coast because land masses contaminate the data.
Recent progress in reprocessing radar waveforms in coastal areas and use of new altimetry techniques (e.g., Ka band altimetry and synthetic aperture radar (SAR) mode) have enabled the satellite community to develop new coastal altimetry data sets.
However, coverage from these products remains uneven in space and time, and efforts are needed to construct a consistent gridded coastal altimetry database with global coverage.

Satellite technology supports the observation and analysis of marine bio-geo-chemical processes at global and regional scale.

This video, produced in 2004, illustrates the activities performed at the Institute for Environment and Sustainability of the Joint Research Centre on the operational use of Earth Observation for marine water quality and climate change investigations.

The MERIS European ocean color sensor was successfully operated onboard the ENVISAT platform from March 1, 2002 till April 8, 2012.

Today European satellite ocean color sensor is called OLCI and operates onboard the Sentinel-3 satellite since mid-2014.

Keeping an Eye on Forcing Agents

To be effective, satellite data must be coupled with in situ measurements; the strengths and limitations of each data source complement each other.
For example, extreme sea levels that result from a variety of oceanic, atmospheric, and terrestrial processes acting on a broad range of timescales are highly correlated with the global mean sea level rise: The higher the global mean rise is, the higher the water elevation is during extreme events [Menéndez and Woodworth, 2010].
Data banks of tide gauge records are valuable sources of information on mean and extreme sea levels, supplementing satellite data.
Version 2 of the Global Extreme Sea Level Analysis (GESLA-2) is the most complete extreme sea level data set assembled to date [Woodworth et al., 2017].
The satellite community has made it a priority to ensure that this activity is maintained and extended in the future.
Although wave models are available at global, regional, and local scales, wave and wind measurements in the coastal zones are still limited.
Altimetry and SAR images can provide such information; however, we need to undertake investigations using existing and upcoming altimeter data sets (in particular using the new SAR mode).
A multisensor approach (altimetry, SAR, and scatterometry) to measuring winds and waves in selected coastal regions could provide much-needed constraints on coastal hydrodynamic and flooding models.

The global mean level of the oceans is one of the most important indicators of climate change.

It incorporates the reactions from severaldifferent components of the climate system.

Precise monitoring of changes in the mean level of the oceans, particularly through the use of altimetry satellites, is vitally important, for understanding not just the climate but also the socioeconomic consequences of any rise in sea level. 

credit CLS

Other forcing agents acting on coastal zones include river runoff, sediment supply, and changes in land use.
Over previous decades, human activities have strongly modified river runoff and sediment delivery to the coastal zone, with great influence on coastal erosion.
Accurate estimates of such quantities are thus crucial.
Satellite altimetry, particularly in ungauged or poorly gauged hydrological basins, now routinely measures the water level on land from which river discharge can be derived.
We can also indirectly estimate river discharge for medium-sized basins (<10,000 square kilometers) from satellite images in the visible and near-infrared spectrum.

The Surface Water and Ocean Topography (SWOT) satellite mission planned for launch in 2021 will improve the characterization of global runoff processes with a 50-meter resolution threshold. Although the capability of remote sensing systems to retrieve land use change is now well established, what’s still missing is an easy-to-use database collecting relevant information with global coverage and long records.

 An acoustic tide gauge monitors the harbor at Burnie on the northern coast of Tasmania, Australia. To its right, a special pillar has a GNSS receiver on top.

Credit: © Commonwealth of Australia (Geoscience Australia) 2016.

Net subsidence and the resilience of many of the world’s significant deltas (home to millions of people, infrastructure, and significant food supply) are the summed response to sediment supply, land subsidence in response to water and hydrocarbon extraction, and land use change.
Techniques like Global Navigation Satellite Systems (GNSS) and interferometric synthetic aperture radar (InSAR) provide invaluable information on land motions at local scales [Allison et al., 2016], but many coastal zones are not equipped with GNSS receivers, and systematic monitoring of land motions by InSAR is still missing in many vulnerable areas such as the low-lying coasts of Pacific islands and subsiding cities of southeastern Asia.
Thus, we need to equip the most vulnerable coastal sites with precise positioning equipment to measure long-term vertical land motions.

CNES video,

outlining how Jason-3 satellite data is used to monitor coastal erosion and predict flooding.

Keeping an Eye on Coastal Evolution

Sediment supply and transport processes drive changes occurring along shorelines and in nearshore coastal zones as well as in river estuaries.
These changes are still poorly quantified in most coastal areas, and coastal observatories developed to track them using in situ and airborne data remain limited.

Here again, space data offer an opportunity to gather additional observations with a global perspective.
Currently, most space-based initiatives are based on a visual processing of high-resolution optical data (0.5- to 1-meter resolution) from imaging satellites.
Errors in georectification (aligning satellite images with maps) and on shoreline indicators lead to an effective precision of 1–5 meters in the shoreline position.

However, because we currently lack automatic techniques for processing these data, no global satellite-based database of shoreline position changes exists.
Automatic analysis of optical images, the use of high-resolution synthetic aperture radar images in cloudy tropical areas, and accurate estimates of shoreline indicators thus represent high-priority objectives for science fields related to coasts.

Global to regional data sets based on ocean color sensors allow us to quantify the dynamics of suspended sediment, which has been related to shoreline changes with some success close to dynamic estuaries such as the Amazon and Mekong estuaries [e.g., Loisel et al., 2014].
However, we need further methodological developments that allow repeated data acquisitions in highly dynamic areas (e.g., estuaries, sandy inlets, and sandy beaches) to improve our understanding of coastal evolution in other types of coastal environments.
For example, suspended sediments are visible in the above satellite image of the Ganges-Brahmaputra Delta.

High-resolution digital elevation models and coastal bathymetric data are other examples of critical data sets needed for a number of applications in coastal zones, including accurate modeling of flooding during storm surges and quantification of coastal morphological changes due to sedimentary processes or human interventions.
A high-precision (~20 centimeters) and high-resolution (~1 to 10 meters) database of continuous marine-land topography and bathymetry would be particularly useful to represent detailed submersion patterns while being consistent with uncertainties of extreme sea level values.

Lidar techniques have enabled important progress, but they still require postprocessing to remove features like trees or vehicles from the raw data.
Repeated bathymetric surveys with wide coverage would be useful to understand nearshore coastal processes.
We expect progress from new techniques such as satellite and drone-acquired high-resolution imagery.
Nearshore bathymetry, shoreline changes, and high-resolution topography are definitely observational priorities, especially along densely populated coastlines.

Putting It All Together

If we are to make progress on understanding the magnitude and causes of changes in the coastal zone on a global basis, we must make considerable investments in space-based as well as in situ observation systems.
Modeling and synthesis activities must accompany the measurements, so that the research can provide insight into the future change of coastal areas.

Finally, access to global coastal data sets is still too limited.
International efforts such as the World Climate Research Programme should consider establishing a data repository gathering all needed coastal observations, whether collected locally or through satellite remote sensing.

Mapping the seafloor

Having detailed knowledge of the shape of the seafloor is essential for generating nautical charts for navigation.

It is also needed for exploration, fishing, coastal management and for understanding ocean currents that transport heat, nutrients and pollutants.

While mapping the seafloor was traditionally carried out using sonar on ships, optical satellite data provide global, high-resolution maps that show ridges, valleys and sediments.

-courtesy of ESA-

Tinkerbelle : Manry's dream

Robert Manry was not a silly dreamer: in 1965, he sail across the Atlantic in a 25 foot sloop
He sailed his tiny sloop, Tinkerbelle, from Falmouth, Massachusetts to Falmouth, England.

Crowds turn out to cheer Robert Manry as he completes his lone crossing of the Atlantic. 

From DuckWorkMag by Bryan Lowe

It was a different time when Robert Manry set out to cross the Atlantic in a 13.5 foot boat.
In 1965 the world seemed consumed by Vietnam.

Manry was just another young father trying to raise a family and earn a living.

He was a copy editor of a good size newspaper.

He had no expectation of fame or financial reward. Even the idea of writing a book seemed no more than a secondary thought.

His goal didn't even seem clear to him.

He had bought a small boat to go on day trips with his family.

Like many of us, he seemed to enjoy working on the boat even more.

He took the modest little day sailer and added a small cabin, cleaned it up, and added some paint.

Seemingly out of the blue a friend asks Manry if he wants to sail across the Atlantic with him in a 25 foot sloop.

The offer was made mostly in jest, but it wasn't seen that way by Manry.

Although it seemed outside his nature, it had been a dream of his for almost 30 years.

Manry immediatly set to work on making the dream come true.

He was even granted time off from work.

His friends thought him a bit daft, but for some reason the idea seemed plausible to many.

Some even said they wished the could go along.

As Robert rolls along through heavy weather, people who knew him describe his voyage...

But within weeks he was alone.
His trip had fallen through and his crowd of would be sailors suddenly had others things to do.
For Manry the dream had gone too far.
Or perhaps he thought of some of his neighbors who had thought him a silly dreamer.
He still wanted to go.
He knew it would be an adventure, but it is clear he had no idea what he faced.
Without telling anyone but his wife and children he set about making plans to take their little family sailboat across the Atlantic alone.

The boat was a poor choice for his mission.
In addition to being too small, it's entire design was for a pleasant afternoon on the lake.
Even with his modest cabin addition, the boat had no business on open waters.
The hull wasn't deep enough... or wide enough... or strong enough.
The cockpit was almost an open shelf offering little protection from the wind or the waves.
There really wasn't enough room for provisions for the long journey ahead.
His ignorance created calm, if not exactly bliss.

This is a rough cut trailer for the documentary film. 

See more at www.robertmanryproject.com.

During his voyage he was remarkably lucky.
What I find so enjoyable about this book is not the blatant bravery or the remarkable hardships.
It is Manry's simple old fashioned charm and enthusiasm.
You get the feeling of sitting in his living room, his wife bringing snacks on the TV tray while the kids watch the latest episode of My Three Sons across the room.
There is no bravado.
His world is filled with people who want the best for him, and he wishes the best for them.
Nature is not put on a pedestal, nor is there a battle of man versus nature.
It's just a bloody nice trip.
Sure his rudder broke... yes there were some 20 foot seas... and yes he did get knocked overboard a few times.
But they seem mere footnotes to his constant enthusiasm and belief that he will make it.
There is no sex.
There are no fights.
There is no doubt.
Manry makes it, and we are there cheering for him as he pulls into harbor surrounded by the press of the World and thousands of well wishers.
The reception a total shock to Manry.
The book is something of a window into the past. It's writing style more akin to the Wind in the Willows than The Perfect Storm.
As I finished the book I wished Manry was still alive for I had many questions.
He seemed such an unlikely person to sail a boat across an ocean.
He didn't have that driving wanderlust or fear of commitment that seems to drive so many others.
What did he do next?
Was this the first in a series of adventures, or did he settle down to a life of family and work?
Why did he do it?

New Greenland maps show more glaciers at risk

UCI’s BedMachine ice mapping technique enabled the creation of a three-dimensional image of a portion of the northwest coast of Greenland.

Ocean bathymetry is shown in blue and ice surface topography are displayed in white and orange.

Mathieu Morlighem / UCI

From UCI

UCI-created high-resolution charts will inform future ice and sea level forecasts

New maps of Greenland’s coastal seafloor and bedrock beneath its massive ice sheet show that two to four times as many coastal glaciers are at risk of accelerated melting as had previously been thought.

Researchers at the University of California, Irvine, NASA and 30 other institutions have published the most comprehensive, accurate and high-resolution relief maps ever made of Greenland’s bedrock and coastal seafloor.
Among the many data sources incorporated into the new maps is data from NASA’s Ocean Melting Greenland campaign.

Lead author Mathieu Morlighem of UCI had demonstrated in an earlier study that data from OMG’s survey of the shape and depth, or bathymetry, of the seafloor in Greenland’s fjords improved scientists’ understanding of both the coastline and the inland bedrock beneath glaciers that flow into the ocean.
That’s because the bathymetry at a glacier’s front limits the possibilities for the shape of bedrock farther upstream.

(a) Data coverage, including ice-penetrating radar measurements (Center for Remote Sensing of Ice Sheets, High CApability Radar Sounder, University of Denmark, Uppsala University, Pathfinder Advanced Radar Ice Sounder, Alfred Wegener Institute) and ocean bathymetry (from single-beam data in dark blue),

and (b) BedMachine v3 bed topography sources, which include mass conservation (MC), kriging, Greenland Ice Mapping Project (GIMP) (Howat et al., 2014), RTopo-2/IBCAO v3 (Jakobsson et al., 2012; Schaffer et al., 2016), and bathymetry data from multibeam and gravity inversions acquired after the compilation of IBCAO v3.

The nearer to the shoreline, the more valuable the bathymetry data are for understanding on-shore topography, Morlighem said.
“What made OMG unique compared to other campaigns is that they got right into the fjords, as close as possible to the glacier fronts. That’s a big help for bedrock mapping,” he added.

Additionally, the OMG campaign surveyed large sections of the Greenland coast for the first time ever.
In fjords for which there are no data, it’s difficult to estimate how deep the glaciers extend below sea level.

(a) BedMachine v3 bed topography (m), color coded between −1500 m and +1500 m with respect to mean sea level, with areas below sea level in blue

and (b) regions below sea level (light pink) that are connected to the ocean and maintain a depth below 200 m (dark pink) and that are continuously deeper than 300 m below sea level (dark red).

The thin white line shows the current ice sheet extent.

The OMG data are only one of many datasets Morlighem and his team used in the ice sheet mapper, which is named BedMachine.
Another comprehensive source is NASA’s Operation IceBridge airborne surveys.
IceBridge measures the ice sheet thickness directly along a plane’s flight path.
This creates a set of long, narrow strips of data rather than a complete map of the ice sheet.

Savissuaq Gletscher area in the GeoGarage platform (DGA chart)

Besides NASA, almost 40 other international collaborators also contributed various types of survey data on different parts of Greenland.

No survey, not even OMG, covers every glacier on Greenland’s long, convoluted coastline.
To infer the bed topography in sparsely studied areas, BedMachine averages between existing data points using physical principles such as the conservation of mass.

Bed topography for different sectors of Greenland:

(a) the region of Savissuaq Gletscher, (b) Hayes Gletscher, (c) Illullip Sermia, (d) Mogens Heinesen N, (e) Heimdal Gletscher, and (f) Skinfaxe.

The yellow/red lines indicate the ice front position between 1985 and today from Landsat data, and the white dotted line shows the profile used in Figure 1.

The topography is color coded between −700 m and 800 m, and contours are shown every 200 m from −800 m to 200 m above sea level.

Some glaciers, such as the one 10 km northwest of Heimdal Gletscher, were not mapped using MC.

The new maps reveal that two to four times more oceanfront glaciers extend deeper than 600 feet (200 meters) below sea level than earlier maps showed.
That’s bad news, because the top 600 feet of water around Greenland comes from the Arctic and is relatively cold.
The water below it comes from farther south and is 6 to 8 eight degrees Fahrenheit (3 to 4 degrees Celsius) warmer than the water above.
Deeper-seated glaciers are exposed to this warmer water, which melts them more rapidly.

Surface and bed topography along six profiles (see white dotted lines in Figure 2) from this study (solid black) and bed from B2013 (dotted red, Bamber et al., 2013) and RTopo-2 (dotted yellow, Schaffer et al., 2016). Multibeam bathymetry data (MBES) are shown in blue.

The vertical lines show the ice front position between 1995 and today.

Morlighem’s team used the maps to refine their estimate of Greenland’s total volume of ice and its potential to add to global sea level rise if the ice were to melt completely, which is not expected to occur within the next few hundred years.
The new estimate is higher by 2.76 inches (7 centimeters) for a total of 24.34 feet (7.42 meters).

OMG principal investigator Josh Willis of JPL, who was not involved in producing the maps, said, “These results suggest that Greenland’s ice is more threatened by changing climate than we had anticipated.”

On Oct. 23, the five-year OMG campaign completed its second annual set of airborne surveys to measure for the first time the amount that warm water around the island is contributing to the loss of the Greenland ice sheet.
Besides the one-time bathymetry survey, OMG is collecting annual measurements of the changing height of the ice sheet and the ocean temperature and salinity in more than 200 fjord locations. Morlighem looks forward to improving BedMachine’s maps with data from the airborne surveys.

The maps and related research are in a paper titled “BedMachine v3: Complete bed topography and ocean bathymetry mapping of Greenland from multi-beam echo sounding combined with mass conservation” in Geophysical Research Letters.
This project received support from NASA’s Cryospheric Sciences Program and the National Science Foundation’s ARCSS program.

Links :

• GeoGarage blog : Greenland’s coasts are growing as seas rise / Global warming is melting the Greenland ice ... / Map provides high-resolution look at ... /