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Greenland is the largest island on Earth, and about 80% of it is covered by a giant sheet of ice. Slowly flowing glaciers connect this massive frozen reservoir of freshwater to the ocean, but because of climate change, these glaciers are rapidly retreating.

I’m an earth scientist who studies how changes to Greenland’s glaciers affect the stability of the ice sheet as a whole. Healthy glaciers are stable in size and shape and act as drains for the ice sheet, transporting ice into the sea. They maintain a balance where the ice added each year roughly equals the ice lost to the sea.

Shrinking glaciers have created a new normal for Greenlands ice

As Greenland’s glaciers retreat, they are losing ice at a faster and faster rate. Image credit: Michalea King, CC BY-ND Michalea King, The Ohio State University

But because of the warming caused by climate change, that dynamic has changed.

For years, scientists have watched as glaciers around the world retreat. But our research has found that the glaciers along the edge of Greenland have retreated so much that they no longer keep the ice sheet that feeds them in balance.

As the glaciers retreat up valleys, they flow faster and bring more ice from inland to the sea. Imagine a traffic jam: When a highway is jampacked with cars – or ice – it flows slowly. But as the jam or glacier gets smaller, the number of cars, or the amount of ice, that can flow by in a given time increases.

Greenland’s ice sheet is now out of balance. The new normal is an annual overall loss of ice.

Changes at the edge, consequences for the whole

Ice sheets are formed when snowfall accumulates over thousands of years and compresses into layers upon layers of ice. But ice is not a perfectly rigid material – it behaves kind of like an extra-thick yet brittle honey.

Once an ice sheet becomes tall enough, the ice begins to flow outward because of its own weight. This ice is funneled down valleys toward the ocean, forming fast–flowing outlet glaciers. These glaciers can move as much as 10 miles per year.

Although glaciers comprise only a narrow region at the edge of the ice sheet, they play a huge role in controlling how rapidly ice is drained from the sheet into the ocean. Generally, a glacier that extends a long distance through a valley will move more slowly and drain less ice from the ice sheet than if it were shorter.

Most of Greenland’s glaciers end at the sea, where ocean water melts and weakens the ice until it breaks off in pieces that dramatically fall into the North Atlantic. If ice is lost at the front of the glacier faster than it is replenished by upstream ice, the glacier will recede inland. This is called glacial retreat.

Retreat not only shortens the length of the glacier but also reduces the friction between the ice and surrounding valleys. With less surface area of ice touching the ground, the ice can flow faster. Much like a shrinking traffic jam, sustained glacier retreat results in faster-flowing glaciers that drain the ice sheet above more rapidly.

A persistent state of loss

Ocean and air temperatures have strong effects on glaciers. Both ocean and air temperatures are rising.

For Greenland’s glaciers, the warming ocean is the biggest cause of glacial retreat. On average the glaciers have retreated about 3 kilometers since the mid-1980s, with most of this retreat occurring between 2000 and 2005.

My colleagues and I used thousands of satellite images to measure changes in length, thickness and flow speed of Greenland’s glaciers. With this information, we found two important things: Glacial retreat is accelerating, and the ice sheet is losing an astonishing – and also increasing – amount of ice each year.

Our team found that today, the glaciers drain 14% more ice from the ice sheet annually – approximately 500 billion metric tons – than they did on average between 1985 and 1999. This faster flow is causing the ice sheet that covers most of Greenland to shrink, but it has also changed the dynamic of the entire system.

The ice sheet is now in a new, unbalanced state of persistent mass loss. Before the year 2000, ice loss roughly equaled the ice added from snowfall, so the ice sheet was stable. Now, ice mass losses consistently exceed mass gains – even in the coolest years of relatively high snow accumulation. The glaciers used to act as an important traffic jam, keeping ice loss in check. Now, however, traffic flows more freely and the ice is able to more easily flow away from the ice sheet.

Unfortunately, warmer air temperatures have also increased surface melt, resulting in less snow now accumulating on Greenland. Given all these factors, my colleagues and I now estimate that the ice sheet may see a mass gain year only once a century.

In serious trouble, but not yet doomed

Our study showed how widespread retreat drove both an increase in glacier discharge and a shift to persistent ice sheet mass loss. But this doesn’t mean the ice sheet is doomed. Continued retreat and further increases in discharge are limited by topography.

[Deep knowledge, daily. Sign up for The Conversation’s newsletter.]

Over the next several centuries, the glaciers may retreat onto higher ground and eventually form a completely landlocked ice sheet with minimal flow – essentially a large chunk of ice sitting on top of Greenland with no glaciers to drain it. Under this future scenario, the balance of the ice sheet would be determined only by surface changes – snow accumulation and surface melt. This loss of ice would equal meters of sea level rise.

At this point, the fate of the ice sheet simply depends on whether it is melting faster than it grows from snowfall. In a warm world where climate change is not addressed, the ice sheet will slowly melt and ultimately disappear. But if climate change is controlled and cooler temperatures are maintained for a prolonged period, it is possible that the Greenland ice sheet could regrow. That day may be hundreds of years into the future, but it is actions made today that will decide the fate of Greenland’s ice sheet.The Conversation

Source: Ohio State University




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Microsoft Windows Virtual Desktop: A cheat sheet

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Cloud-based DaaS offers several advantages to a remote workforce. This smart guide to Microsoft Windows Virtual Desktop assesses the platform and what it can offer.

Image: iStock/DragonImages

Unprecedented conditions surrounding COVID-19 and the accompanying global pandemic have left many business enterprises scrambling to find ways to accommodate an increasingly remote and virtual workforce. Some businesses have discovered that workforce productivity is the same, if not better, under a virtual scheme. These enterprises are likely to adopt platforms like Desktop as a Service (DaaS) and virtual desktop infrastructure (VDI) going forward, even after the pandemic has subsided.

SEE: TechRepublic Premium editorial calendar: IT policies, checklists, toolkits, and research for download

Cloud-based DaaS and VDI services are offered by a number of vendors including Microsoft through its Azure cloud platform. Microsoft Windows Virtual Desktop is offered as a free service to certain Microsoft 365 and Azure subscribers. Licenses for individual Windows Virtual Desktops are also available with costs that vary with server location and type of virtual machine.

The are many advantages to Windows Virtual Desktop, but there are also several caveats to consider before your business decides to adopt the platform. Like all business decisions, planning and analysis before making any decisions is warranted and highly recommended. This Microsoft Windows Virtual Desktop: A cheat sheet from TechRepublic will help you assess what the platform is and what it can offer, so you can make the best decision possible for your business.

SEE: All of TechRepublic’s cheat sheets and smart person’s guides

What is Windows Virtual Desktop?

Leveraging the power of Microsoft Azure, Windows Virtual Desktop is an instanced virtual machine hosting a desktop and app virtualization service running on the cloud. Windows Virtual Desktop delivers a virtual desktop experience and remote apps to any device. Depending on how it is configured, the platform can bring together Microsoft 365 and Azure to provide users with a multi-session Windows 10 experience, which includes scaling and reduced IT costs.

Windows Virtual Desktop can be configured to run Windows 10 Enterprise, Windows 7 Enterprise, or Windows Server 2012 R2, 2016, 2019. Windows 8 and Windows 8.1 are not supported.

The following Remote Desktop clients support Windows Virtual Desktop:

SEE: Software as a Service (SaaS): A cheat sheet (free PDF) (TechRepublic)

Why is Windows Virtual Desktop important?

Whether out of necessity or as part of an overall productivity strategy, the modern workforce is increasingly a remote and mobile workforce. To gain access to the systems and applications it needs to do its jobs, the workforce grows more and more dependent on cloud platforms and virtual machines which can be accessed from anywhere, at any time, by any device.

Windows Virtual Desktop provides a workforce with access to a virtual Windows computer running whatever apps a typical IT-sanctioned Windows computer should be running for your business. By taking advantage of Azure’s cloud infrastructure, businesses can setup multi-session Windows 10 deployments optimized to run in multi-user virtual scenarios.

From a worker’s perspective, their Windows Virtual Desktop is exactly the same as a traditional PC setting on their desk. From the enterprise’s perspective, the cost of purchasing, setting up, deploying, and securing physical hardware can be saved by entrusting Microsoft and Azure to handle those specifics in the cloud.

SEE: Microsoft sees surge in demand for cloud services during coronavirus outbreak (TechRepublic)

What are the benefits of Windows Virtual Desktop?

Whether by choice or by happenstance, if your employees are working remotely, sensitive company data will likely be transferred and stored locally at some point, even if only briefly. Even with best practice security precautions, this transfer of sensitive data is risky. Add the variabilities of employees using their own personal devices and networks for work activity and you have a recipe for disaster.

Windows Virtual Desktop allows employers to deploy virtual machines, configured exactly how they need them to be, that are securely instanced in the Azure cloud. In essence, sensitive company data is never transferred out of the company’s control structure because any data transfers are merely between Azure cloud instances. Within the Microsoft Azure cloud, data is protected by all manner of built-in security protocols, including Azure Firewall, Azure Security Center, Azure Sentinel, and Microsoft Defender ATP.

SEE: How SMBs build their tech stacks (TechRepublic)

Under Windows Virtual Desktop, access to desktop instances is controlled by conditional access protocols, including multi-factor authentication. Azure infrastructure can be deployed to enable role-based access control (RBAC) and detect threats using Azure Security Center. Windows Virtual Desktop certified compliant with ISO 27001, 27018 and 27701, PCI, FedRAMP High for Commercial, and HIPPA.

If your enterprise already subscribes to Microsoft 365 or an enterprise version of Windows, it can establish a desktop instance for each user for free with Windows Virtual Desktop. Therefore, at no extra charge, your remote users can access a ready-made virtual machine running Windows from anywhere, at any time, from any device.

Because Windows Virtual Desktop is managed through the Microsoft Azure Portal, your enterprise can scale desktop instances to meet business needs on the fly. Admins can increase virtual CPUs, add virtual RAM, allocate more virtual hard disk storage, etc., with a few mouse clicks and an admin login account.

What are the caveats of Windows Virtual Desktop?

The primary caveat to consider when deciding whether to deploy Windows Virtual Desktop for a remote workforce is the quality of network connections. No matter how well you plan and design your virtual desktop instances, they are only worth the effort if your employees have the ability to effectively reach the cloud. Slow internet connections, intermittent connections, and no internet connections are all a real possibility, and all must be mitigated for cloud-based virtualization to work efficiently.

SEE: DaaS and VDI: New report underscores the high costs and challenges of virtual workforces (TechRepublic)

Beyond the technical aspect of network connections, employers must also consider how much employee training will be necessary. Tech-savvy employees and IT pros will likely have no trouble connecting to Azure and Windows Virtual Desktop servers, but some employees may need at least some instruction to complete the connection. Who will provide that help, how will they provide it, what if it is not effective? These questions must have acceptable answers.

Other questions to be answered include, once in operation, how will employees ask for additional resources if they need them? Will there be a ticketing system with IT department personnel responsible for their resolution? Is that infrastructure in place? Setting up procedures to handle the maintenance of a Windows Virtual Desktop system should be completed before deploying the actual virtual instances.

Who are the major competitors to Windows Virtual Desktop?

Competition among cloud vendors in the virtual desktop space is fierce and includes dozens of different companies, many of which are prominent and familiar. Obvious competitors include the usual major cloud services suspects of Amazon AWS and Google Cloud Platform. Other prominent competitors include Citrix and VMware. Other smaller competitors offer specialized desktop services for engineers, architects, artists, and scientists that require specific features.

SEE: Research: SMB IT stack decisions based on fulfilling business needs (TechRepublic Premium)

Here is a short list of virtual desktop competitors:

With all of this competition, Microsoft will continue to feel pressure to keep costs and fees low for its Windows Virtual Desktop service. This competitive pressure helps explain why Microsoft is willing to offer Windows Virtual Desktop free to existing customers already subscribed to Microsoft 365 or enterprise versions of Windows.

How do you get Windows Virtual Desktop, and when will it be available?

Windows Virtual desktop is available through the Microsoft Azure Portal. For current subscribers to Microsoft 365 and enterprise versions of Windows, desktop instances are available for each user at no extra charge. Non-subscribers will have to pay a subscription fee determined by the specifications of the virtual machines used for each desktop instance.

Subscribers to these existing services have free access to Windows Virtual Desktop instances running specific operating systems on a per user basis:

Operating system

Required license    

Windows 10 Enterprise multi-session or Windows 10 Enterprise    

Microsoft 365 E3, E5, A3, A5, F3, Business Premium or Windows E3, E5, A3, A5    

Windows 7 Enterprise    

Microsoft 365 E3, E5, A3, A5, F3, Business Premium or Windows E3, E5, A3, A5    

Windows Server 2012 R2, 2016, 2019    

RDS Client Access License (CAL) with Software Assurance    

For enterprises without a pre-existing subscription, the price of a Windows Virtual Desktop through Azure will depend on the specifications chosen for each desktop instance. For example, a pay-as-you-go instance with 2 CPUs, 8 GB RAM, and 50 GB of storage is estimated to cost $137.29 per month. A quote from the Azure price calculator that is significantly more than a Microsoft 365 Business Premium subscriber paying $12.50/month/user.

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Scientists are getting closer to effective treatment for hair loss

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Hair loss seems like a minor problem to many. You got bald, so what? Some people prefer this look. However, for many men going bald is a terrible experience and they would pay good money to avoid it. Now scientists at the University of Helsinki have identified a mechanism that is likely to prevent hair loss.

Many men lose their hair as they grow older. It is natural and hereditary – if your dad or one of your grandads went bald, chances are your head is going to be very shiny in the future. On the other hand, ultraviolet radiation and other environmental factors damage our skin as well.

Scientists are getting closer to effective treatment for hair loss

Baldness can be a serious psychological drag – some men got to huge lengths to hide it. Image credit: Nesnad via Wikimedia (CC BY 4.0)

Stress is another factor as well as various diseases and some treatments. Scientists in Finland now think that hair follicle stem cells, which promote hair growth, could live longer if their metabolic state was switched. And scientists already managed to demonstrate that in experiments with a Rictor protein.

Naturally, an average human sheds 500 million cells and a quantity of hairs weighing a total of 1.5 grams every day. If you are not going bald already, this tissue is replaced by specialised stem cells. If these stem cells become inactive or at least less active, lost tissue is not going to be replaced and hair follicles are going to become weaker and smaller. Normally, as a hair follicle becomes older and weaker, stem cells replace it with a new one and then return to their specific location and resume a quiescent state. If this cycle could be maintained, baldness would be essentially cured.

1603134795 223 Scientists are getting closer to effective treatment for hair loss

Hair follicle stem cells, which promote hair growth, can prolong their life by switching their metabolic state. Image credit: Sara Wickström, University of Helsinki

Scientists now found that stem cells need a change in the metabolic state in order to return to their specific location. Essentially, they switch from glutamine-based metabolism and cellular respiration to glycolysis – this switch is induced by a protein called Rictor. Scientists found that when Rictor is absent, slow exhaustion of the stem cells and age-related hair loss begins. Experiments with mice showed that Rictor deficiency results in hair loss.

Sara Wickström, lead author of the study, said: “We are particularly excited about the observation that the application of a glutaminase inhibitor was able to restore stem cell function in the Rictor-deficient mice, proving the principle that modifying metabolic pathways could be a powerful way to boost the regenerative capacity of our tissues”.

Baldness is a minor issue – it is not life threatening and some people can really rock that look. But it can be a serious drag psychologically and it would be worthwhile to fix it. Also, scientists can use this opportunity to learn more about stem cells, their function and regenerative functions. This could benefit the entire aging research field.

 

Source: University of Helsinki




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Apple Offering Free Virtual Workshops in India on Photography, Art, Music, and More

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Apple is hosting a series of free virtual sessions in India under its ‘Today at Apple’ initiative. Nearly month after the online Apple Store launched in India, the tech giant will be commemorating the occasion by offering free virtual workshops related to photography, music, art, and other creative fields. The workshops began on October 17, and will continue till November 29. Today at Apple was launched as a retail-focused initiative back in 2017, but this is the first time it is being extended to India.

While under ordinary circumstances, consumers visit Apple’s retails stores for the Today at Apple sessions, this year the workshops are being conducted online worldwide, due to the coronavirus pandemic. Starting from 2017, Today at Apple conducts hands-on sessions with experts on basics, how-to-learn, and professional-level programmes on topics ranging from art, coding, design, music, photography, and more. The workshops in India will kick-start with sessions from local photographers and acclaimed musicians, with tips on skills and techniques from Apple Creatives.

The photography workshops for the coming weeks include sessions with Siddhartha Joshi, Avani Rai, Anurag Banerjee, Prarthna Singh, and Hashmi Badani. Music sessions so far include a beginner’s course to Garage Band. The full schedule can be found here. The music skill sessions will also include sessions by Lisa Mishra, DIVINE, Aditi Ramesh, Raja Kumari, and Prateek Kuhad soon.

The first session of the Today at Apple series in India is Photo Lab: Faces and Places with Mumbai-based photographer Siddhartha Joshi, on October 22. He will be showcasing portrait projects he has taken across India, and giving professional photography tips.

You can head to Apple India and sign up for these sessions. To join a Webex session, you need a mobile/ laptop/ tablet/ computer, along with a stable Internet connection and the free Cisco Webex Meetings app. If you’re under 18, your parent or guardian can register for you, as per Apple. To recall, Apple Store launched in India in late September, and the company had that point itself announced plans to bring Today at Apple to India.

“We’re creating a modern-day town square, where everyone is welcome in a space where the best of Apple comes together to connect with one another, discover a new passion, or take their skill to the next level,” Angela Ahrendts, Apple’s senior vice president, Retail had said at the time of launching Today at Apple in 2017.


Are iPhone 12 mini, HomePod mini the Perfect Apple Devices for India? We discussed this on Orbital, our weekly technology podcast, which you can subscribe to via Apple Podcasts, Google Podcasts, or RSS, download the episode, or just hit the play button below.

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