Climate News Network

Carbon cuts will not prevent sea level rise

January 16, 2017, by Tim Radford

Tuvalu looks serene today, but like many Pacific islands risks inundation by the rising sea.
Image: INABA Tomoaki via Wikimedia Commons

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Short-lived greenhouse gases will continue to affect the oceans for centuries however much the world achieves by carbon cuts.

LONDON, 16 January, 2017 – Even supposing the world does make dramatic reductions in carbon dioxide emissions, the fate of the small island states remains uncertain

New research suggests that other, more short-lived greenhouse gases in the atmosphere could drive the thermal expansion of the oceans for centuries to come.

This is grim news for those low-lying coral atoll nations in the Pacific already threatened by sea level rise.

They fought at the Paris summit in 2015 for world agreement on a reduction of emissions that would keep global warming to 1.5°C above historic levels. But a new study, in the Proceedings of the National Academy of Sciences, suggests that may not be enough.

“If you think of countries like Tuvalu, which are barely above sea level, the question that is looming is how much we can emit before they are doomed. Are they already slated to go under, even if we stopped emitting everything tomorrow?” said Susan Solomon, professor of atmospheric chemistry at the Massachusetts Institute of Technology.

Inevitable rise

“It’s all the more reason why it’s important to understand how long climate changes will last, and how much more sea-level rise is already locked in.”

Sea levels are rising as glaciers the world over retreat and Arctic icecaps melt, in response to rising carbon dioxide levels in the atmosphere, as humans burn fossil fuels. 

But this time the MIT team applied their climate model not to carbon dioxide, but to the other greenhouse gases, among them methane and the chlorofluorocarbons. They then fed into the simulation the effect of heat on water, which expands with temperature.

And the short-lived gases are potent: the finding says that even if the production of these ceased entirely, at the end of 100 years three-fourths of the thermally-driven sea level rise would still be there, washing over low-lying coasts, drowning estuaries and river deltas, and seeping into the coral bedrock of islands too small even to register on the global climate maps.

And this slow enduring threat is what the small island states have feared most. They know that their citizens cannot survive if the sea levels rise to the heights predicted in the worst-case scenarios, but it isn’t clear where they could go to escape. They have already been warned that even the Paris Agreement may not be enough to save them.

“ . . . you don’t just get to stop emitting and have everything go back to a pre-industrial state. You are going to live with this for a very long time”

Carbon dioxide is an enduring molecule: even if emissions ceased now, the quantities already emitted will go on warming the world for another 1,000 years. So the effects of fossil fuel combustion are irreversible in the scales of human lifetimes.

But the new research shows that the short-lived gases have long-term consequences as well. Chlorofluorocarbons were banned by the Montreal Protocol nearly three decades ago: had the ban been delayed to 2050, then by 2100 they would have added 14 cms to the overall sea level rise, the authors calculate.

The scientists also tested methane in their simulation: suppose the world went on emitting at the current rate until 2050, 2100, or 2150 and then stopped completely?

In all three scenarios the methane cleared quickly, and atmospheric warming slowed. But ocean warming continued for centuries, and with it, sea level rise. And the later the emissions ceased, the longer the seas stayed high.

“Amazingly, a gas with a 10-year lifetime can actually cause enduring sea-level changes,” Professor Solomon said. “So you don’t just get to stop emitting and have everything go back to a pre-industrial state. You are going to live with this for a very long time.” – Climate News Network

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  • The problem of global warming can be solved in a fairly short time and with reasonable cost but we must act globally in the world, completely changing energy systems and water treatment, to switch to energy interactive with the environment, especially hydroelectric pressurized with air compressed, which costs very little and dissolved oxygen in the water. Precisely because of its very low cost, we can produce artificial rains in the sewer system, with water to be purified and rainwater, where stratifies the CO2 that is heavier than air in the presence of calcareous material, producing calcium carbonate and magnesium that remove CO2 to urban and produce alkaline water environments that fight acidification of the seas. But there are always other solutions related to intelligent management of water through the pump change and the construction of plants that have never been made for incredible oversights of science and designers of the power equipment and water treatment, of which the undersigned is occupied for two decades but in modest roles as technical installer and developer of details. Wrong choices are very old.
    In fact, at the time they were born first thermal engines, thermal power plants, water purifiers, it was also born hydropower and compressed air. But energy development focused only on the thermal sector, which has an average yield of 0.35 relative to the lower calorific value of the fuel. Even nuclear energy is based on the use of the heat, but with disastrous results from an economic and environmental point of view. Although solar energy is based on the use of the heat but with low yields and discontinuous, not universal and not feasible in all parts of the world. Wind energy instead uses the wind force but to produce the pressure of 0.83 bar on wind turbines should be a wind traveling at 80 kilometers per hour. Therefore also this energy is cumbersome and discontinuous with low yields. After 150 years of wrong energy history, the undersigned that is a simple pensioner, has created the SPAWHE website, which was to be called only SP (synergy plants), because, dedicated to the cleaning of fossil energy and then to change the depurative system which were to accompany the production of energy for purifying water and air together. Unfortunately, the world responsible for the environment and energy did not like that a pensioner to look after these issues of their exclusive domain, and they never responded and agreed solutions, which are not the result of fantasies but a work of forty years industry and the environment. Since myself was and is also worried about ocean acidification, also it wanted to bring environmental solutions to be implemented directly in the seas, being inspired to the natural circulation of water, which in certain conditions, brings to the surface the organic sediment precipitates in the seabed, creating phytoplankton, which in turn creates zooplankton and marine food chain. In fact, for myself, it is possible to realize artificial water currents that not only raise the organic nutrients but also the dissolved carbonates in the deep sea and then, in addition to the creation of the food chain where do not exist, we can also increase the alkalinity and combat acidification. In this way is born the AW sector (artificial welling). All this is written in, Also in this case, the silence of the environmental authorities has been eloquent: pensioners should mind their own business without interfering in reserved matters only to them. However, even these reflections and environmental proposals, made illegally, without observing the caste system, have led myself to investigate on the third unexplored world energy sector. Thus was born the third sector of SPAWHE: HE (hydroelectric energy with water recycling). In fact, the existence of ocean currents has opened the mind to myself of the opportunity to produce energy by recycling the water, because inside the volume of water accumulated you can harness the energy position of the water surface respect to water placed in the bottom, as long as there is content to use only the water specifically ducted from the surface, pulled down by a pump inverted, placed in the bottom, which feeds a turbine. This system does not exploit the hydrostatic pressure of the basin but the dynamic pressure that develops in the descent tube due to the rotation of the pump. The turbine, placed after the pump slows down the velocity of water in the descent tube, that would assume the value (V = √ 2 gh) increased by the force of gravity and by atmospheric pressure, that the pump would not be able to control by itself, producing hydroelectric energy instead of dissipating it as heat both in the downhill tube, both in the submerged outlet. The concept of energy of position without the hydraulic jump is understandable even by the drilling of a submerged water vein that spontaneously produces the water output from the subsoil to the effect of atmospheric pressure acting on the water surface of the basin that feeds the vein. In the compressed hydroelectric, we use the same energy principle, but replacing the atmospheric pressure with an artificial pressure, which can be thirty – forty times higher than atmospheric pressure, thereby producing an energy thirty – forty times higher. But to produce energy by recycling the water and without consuming the air cushion is necessary to circulate the water inside the pressurized tank one-way, not like the current autoclaves, where the water comes in and out by the same hole by expanding and compressing the air cushion. The expansion involves a loss of energy, because it requires a subsequent compression and therefore there is not an energy gain. Instead, the energy gain is obtained by circulating, in one way, a part of the water incompressible under the compressed air cushion keeping constant the two volumes inside the tank. Therefore, we only exploit the water that comes from the pressurized tank, as if it came from the overflow of a reservoir at atmospheric pressure, but since the pressure is much higher than atmospheric and replaces the height h in the formula (V = √ 2 gh), we have a multiplication of energy produced in the turbine that is proportional to the pressure of the air cushion, which does not lose its thrust because it does not expand, as it not expands the atmospheric pressure on open basins. For this to happen, it is necessary that the amount of water that enters into pressurized tank is exactly equal to that leaving powering the turbine. This takes place by means of the pump with the double separate power supply up to the impeller, specially invented by myself, which has the power that has the power to recycle the water in two separate circuits aspirants, but with only one outlet placed in the pressurized tank. Therefore, the internal recycling circuit of the pressurized tank is balanced by the static pressure of the air cushion, which acts in the impeller of the pump suction and delivery, while the other power supply of the impeller, hermetically separated from the first, when the impeller rotates, makes enter in the pressurized tank also the water discharged into an open tank from the turbine. But the pressurized tank having already occupied the volume of water and the air cushion expels again the same amount of water which enters, with all its strength, without expanding the air volume, allowing it to enter back into the turbine, in an infinite loop. Obviously, this circuit can be realized in many versions and in many sizes to produce energy, fixed and mobile, in proportion to the pressure of the air cushion (which as is known has a critical pressure of 37.5 bar and a critical temperature of – 140,6 degrees Celsius), therefore, we could produce energy at very low cost, even at the north pole, in all seasons, for twenty-four hours a day and three hundred sixty-five days a year, since the advent of the industrial age, saving spaces pollution and global warming. Indeed, since, proportionally, to the operating pressure, the water solubilize also the gases present in the air, being important only that the nitrogen percentage is neutral and oxygen, thanks to the latter, with this type of energy, we can practically eliminate the costs of depuration because producing energy with rainwater and waste, continuously, practically without energy costs, we arrive easily endogenous oxidation that consumes all organic substances in the water and if we create artificial rain of calcareous materials in covered environments, in the lower areas of the atmosphere, we can lower the quantity of CO2 in air producing alkaline water, which returns to the sea through rivers fighting acidification and melting glaciers. All this is written in many files:,,,,,,,, ns-for-the-marrakech-summit/,,,,,,,,,,,,,,,,,,,,,,
    In the current state of the art in different parts of the world have been realized reversible machines (pumps, turbines) able to operate with good returns both as turbines in a direction of rotation and both as a pump in the reverse direction. But the implants made with these machines do not bring any energy advantage. For myself, only exacerbate the costs, having to carry two large basins, upstream and downstream of the machines. The only advantage that carry the reversible machine is the water recovery to produce energy by day and lift the water at night, when there is less absorption of energy from the networks. This small advantage involves high investment and higher energy absorption because the reversible machines have higher yields when operating as turbines and lower yields when working as pumps, lifting back the water to the upper reservoir. While, the hydro-power secret with the water recycling is to separate clearly the circuit that produces energy by means of dynamic pressure ducted that feeds the turbine, from the circuit that recovers the water drained from the turbine, which must be lifted with very low cost to the upper basin. This is possible only if the hydroelectric plants are realized otherwise: recycling, instantaneously, the water that produces energy in the turbine passes through a very small gathering basin and by inserting it into the upper reservoir recycling circuit, just as small in size, always maintained at the maximum level, which drains the water that feeds the turbine from the overflow. In this way we eliminate completely the energy costs for water lifting and replacing them with the expenses for water recycling, which are hundreds of times lower. In fact, the recycling of 1000 L / s in a DN 800 one circuit with an equivalent length of one kilometer requires a prevalence of the pump about 1.5 m, with a relationship of convenience between recycling and lifting of 1 to 666 (1000 / 1.5), which can become even more convenient by increasing the pipe diameter and less convenient by reducing the diameter. But to enter the water of the basin in the bottom of the upper reservoir recycling circuit is required to the invention of the subscribed called “double pump with separate power supply until to the impeller”, which, with only a suction side of the recycle of the water basin upper, balancing the pressure upstream and downstream of the pump impeller while with the second suction mouth, hermetically separated from the first, in the same impeller, introduces the water of the lower basin. So not only we have to change the hydro power plants but also the water lifting pumps.

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