Tag Archives: climate change

Fighting Climate Change by Capturing Excess CO2.

Posted on November 23, 2020 by | Leave a comment

Climate change is becoming a serious issue as temperatures continue to rise due to increasing global greenhouse emissions. Greenhouse gases such as CO2 trap reflecting sunlight and radiation that would normally escape the atmosphere of Earth and this trapped heat then leads to warmer temperatures. Over the past 150 years, Carbon dioxide(CO2) emissions around the world have increased mainly due to human involvement through the burning of fossil fuels and industrial processes. The figure below outlines the percentages of various greenhouse gas emissions and their sources.

Credit: IPCC(2014)

Due to these rising emissions, there are many researchers and technology companies around the world that are looking at ways to reduce the amount of atmospheric CO2 and mitigate climate change before it is too late. In the past few years, many new technologies and techniques to capture excess carbon have emerged. Some of these main ones include Bioenergy with Carbon Capture and Storage(BECCS or bio-CCS) and Direct Air Capture(DAC). Although the ultimate goal of both methods is to reduce carbon emissions, BECCS focuses on capturing CO2 released through combustion in industrial facilities while DAC aims to directly capture excess CO2 from the atmosphere. From these two methods, companies such as Carbon Engineering who are employing DAC have gained more traction as they have landed large investors such as Bill Gates and Chevron.

A study posted in 2018 outlined the process and cost of Direct Air Capture(DAC). Through this research, a Canadian company called Carbon Engineering based in Squamish, BC has tested the Direct Air Capture technology and hopes to make various large scale carbon storage plants over the next few years. Another company called Climeworks based in Switzerland is using similar methods to capture carbon from the atmosphere. Carbon Engineering has a plan to use the carbon from the atmosphere in 2 different ways which are reusing the stored carbon as a source of fuel and the second being storing solid carbon underground. According to the company, one large scale plant can store as much carbon as 40 million trees. They believe it is an efficient way to reducing carbon emissions and as they continue to get more funding they become closer and closer to their goal.

This video below explains the Direct Air Capture(DAC) method of removing CO2 and also outlines the various ongoing and future projects to mitigate climate change.

-Sandeep Singh

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HOW CLIMATE CHANGE IS MAKING HURRICANES SCARIER

Posted on November 16, 2020 by | 1 comment

The Greatest Storm on Earth

When thinking about powerful natural events on Earth, one might think of raging tornadoes, or blizzards that can shut down cities, but the power of a hurricane is so immense, that they can release up to 10000 nuclear bombs worth of energy of the course of their lives. The power of these natural storms is so great, they are sometimes even visible to Earth even from other planets in our solar system, take the Great Red Spot of Jupiter for example. On Earth, generally hurricanes start to develop in areas of high humidity and relatively warm surface water temperatures, mixed with faint winds. This is why “hurricane season” is generally in the summer and early fall in the northern hemisphere. Hurricanes are devastating to the terrain and any infrastructure caught in their path, and as such is an important issue for people who live in areas known that are likely for hurricanes to hit. The video below from National Geographic goes over some of the specifics when it comes to how a hurricane is made, for further info on the topic.

Hurricane Decay

Eventually, when hurricanes hit land they will slowly start to decay, as the moisture from warm ocean subsides, the hurricane has nothing fueling it, as hurricanes require moisture and heat to continue on. After being cut off from the ocean, the decrease in moisture level also contributes to an simultaneous decrease in the hurricanes intensity.

In the scientific literature, there are already studies looking at how climate change affects hurricanes, and particularly how climate change affects the intensification of some tropical cyclones, but until recently, the question of how the intensity decay was being affected by climate change remained unanswered.

A hurricane at the start of hurricane season / Taken from Flickr user militarymark2007

The Findings

Recently, researchers Lin Li and Pinaki Chakraborty of the Okinawa Institute of Science and Technology have determined through an analysis of historical climate data, alongside computer simulations, that climate change is contributing to the slower decay of hurricanes after landfall. By checking through the hurricane intensity data gathered over the last 50 years in the North Atlantic, they found that “hurricane decay has slowed… in direct proportion to a… rise in the sea surface temperature”. Looking back to the late 1960’s, an average hurricane then would lose around three quarters of it’s intensity a day after it made landfall, whereas an average hurricane now would only lose around half of it’s intensity a day after making landfall. By using computer simulations, they determined that the higher sea surface temperatures are causing the slower decay rate, as the moisture level is now also higher, alongside the amount of heat to fuel the hurricanes ‘engine’, leading to a longer and stronger hurricane after landfall.

Looking Ahead

As we look forward, strategies to mitigate climate change and reduce global warming might become top priorities in a world with an ever increasing climate, and unfortunately now, with even stronger hurricanes.

Hurricane as seen from the ISS by Astronaut Ed Lu. By Image courtesy of Mike Trenchard, Earth Sciences & Image Analysis Laboratory, NASA Johnson Space Center. – http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=12140, Public Domain, https://commons.wikimedia.org/w/index.php?curid=625449

 

– Mehdi Mesbahnejad

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The Future of Antarctica

Posted on November 15, 2020 by | Leave a comment

In September 2019, the Amery Ice Shelf in Antarctica produced its biggest iceberg, which beat the record 50 years ago. The massive iceberg named D-28  covers an area of 1,636 sq km, which is slightly more than half of the Metro Vancouver area. It is about 210 m thick and contains 315 billion-tonne of ice.

Iceberg D-28 breaks away from the Amery Ice Shelf. Credit: ESA

 The cause of iceberg D-28 calving?

As a matter of fact, global warming, caused by greenhouse-gasses emission, has contributed to ice melting around the world. It is interesting to note that the calving of D-28 was a part of the normal cycle of ice shelves.

Firstly, glacier gradually moves toward the ocean by its own weight. As the glacier flow, the friction with the bedrock and surface melting thinning the ice sheets and form ice shelves, which are the arm of the ice sheet. Moreover, the warm circumpolar deep water flows in and melts the ice under the ice shelf that weakening its strength. Thus, the plane of ice starts splitting and shedding into icebergs.

Formation of icebergs. Credit: Calvin Pan

Climatic impacts of the iceberg

Melting icebergs influence both global sea levels and ocean salinity. If iceberg D-28 completely melted, researchers projected that sea volume would increase by 2.6 % compared to the volume of saltwater that was displaced. Annually, the global sea level is rising by about 3 mm, whereas the melting of D-28 only accounts for 0.049 mm of increase per year. As such, an individual iceberg would not dramatically raise the sea level. In considering the ocean salinity, indeed, the melted ice would dilute the salt concentration in the ocean and decline its salinity. This process usually occurs at lower latitudes when the iceberg melts. Nevertheless, at higher latitudes (eg, near where the iceberg breaks off), seawater is frozen by nearby icebergs, and its freezing process increases the salinity. The stabilizing influence on ocean salinity promotes the convection and circulation of oceanic currents.

Will climate change alter the Antarctic landscape?

Yes, climate change will accelerate the loss of Antarctic glaciers due to various reasons. For example, warmer sea, higher air temperatures, and higher sea levels fasten the natural cycle of ice shelves. Watch this short video made by Vox to understand the association between glaciers loss and climate change using the example of Thwaites Glacier, as well as possible consequences.

A study has proposed that reducing greenhouse-gas emissions could possibly mitigate the rate of change in Antarctica. Losing antarctic ice will not only raise the sea level but also threaten wildlife and food security because of more frequent extreme weather. Before dealing with an irreversible change in Antarctica, we must start thinking of how we can save the Antarctic ecosystem.

-Calvin Pan

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Mitigating Climate Change: Carbon Capture

Posted on October 5, 2020 by | Leave a comment

Climate change is the change of weather and the rise of sea levels on the planet Earth. Climate change is an extremely relevant global issue since it can lead to flooding and extreme weather conditions which can endanger life on earth. As a result, it is of utmost importance to find solutions that can help mitigate the effects of climate change. One of the main causes of climate change is the release of excess carbon dioxide into the atmosphere, due to the burning of fossil fuels.

Image: Climate Change
Source: CC0 Public Domain

A solution to climate change

One solution that scientists have proposed in order to reduce the amount of atmospheric carbon dioxide is to capture carbon dioxide in the air and use the captured carbon dioxide as a source of chemical carbon for other processes. This process is known as “carbon capture and utilization” (CCU). Although the potential benefits of CCU are very promising, changing the carbon dioxide into a different form and using it in other chemical processes has been proven to be difficult, mainly due to the thermodynamic stability of carbon dioxide. Although CCU has gained major traction over the past few years, it will still require a lot of time before it can be used industrially worldwide. Scientists are currently in the process of trying to find the least costly, and most efficient means of capturing carbon emissions to reduce climate change. 

YouTube Preview Image                                                      Video: Carbon Capture Plant in Squamish, BC

Carbon capture methods

One of the carbon capturing methods that has been showing promise in recent scientific studies, is the adsorption of carbon dioxide through the use of solid sorbents. Adsorption is the adhesion or the clinging of gas molecules onto a surface. In this case, the carbon dioxide molecules will stick to the solid surface of the sorbent, which leads to successful carbon capturing. The solid sorbents used in this method can be made of “porous carbonaceous materials, zeolites, alumina, silica, (or) metal-organic frameworks.” Adsorption of carbon dioxide can be categorized into two variations; physical and chemical adsorption. In physical adsorption, the transfer of carbon dioxide into the solid sorbent occurs due to the van der Waals interactions between the sorbent and the carbon dioxide. The issue with these physical sorbents is that they have “poor selectivity for CO2, and low CO2 adsorption capacities.” A means of improving both the carbon dioxide selectivity and the carbon dioxide adsorption capacities of these sorbents is by adding basic groups to the sorbent surface, which can strengthen its interactions with the acidic carbon dioxide. These sorbents primarily use alkalis to act as basic groups. In terms of alkali-based sorbents, scientists have been favouring the use of potassium carbonate and sodium carbonate. Although carbon dioxide absorption via solid sorbents is very promising, more scientific work needs to be done to improve the adsorption capabilities of sorbents.

Another carbon capturing method that scientists have been favouring is the separation of carbon dioxide via membranes. These membranes are selectively permeable to carbon dioxide which leads to separation of carbon dioxide from other chemicals.

All in all, the development of these innovative carbon capturing mechanisms is helping to mitigate climate change and scientists are working hard to refine these techniques. 

– Yoshinao Matsubara

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