Kerim Hestnes Nisancioglu
Professor of Climate Dynamics at the Department of Earth Science at the University of Bergen and the Bjerknes Centre for Climate Research
https://kerim.b.uib.no @nissenjo #FLclimatechange
Location Bergen, Norway
Activity
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Kerim Hestnes Nisancioglu made a comment
Thanks for all the questions so far. Based on feedback also here in Bergen there was a request for additional resources on natural radiative forcing and in particular Milankovitch and Orbital insolation.
In addition to the NASA insolation program:
https://climate.nasa.gov/news/2948/milankovitch-orbital-cycles-and-their-role-in-earths-climate/and the...
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Dear @AngieLintott thanks for your comment, we will consider this for the feedback video for this week. There is also a good course on FutureLearn by Time Lenton who has worked quite extensively on the topic of tipping points in the climate system.
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Hi @KimGreen - we agree, the recommended reading and exercises are ment for those who want to go in depth and are at the university level when it comes to math and physics understanding. We use the same content for our Bachelor students in the natural sciences here in Bergen.
We are working on a simplified version of this course which will be extended with...
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Hi @DonnaClark yes - sometimes confusing that positive feedback mechanisms amplify the initial perturbation, which can cause a runaway effect which is 'negative' for climate. Fortunately there are many negative feedback mechanisms in the climate system keeping the system relatively stable.
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Thanks @AilinO for the great questions. Deep water is created at high latitudes as the water turns dense and sinks. This is way at forms the deep water masses of the ocean, most of it is created in the North Atlantic/Nordic Seas an around Antarctic in the Southern Ocean.
It resurfaces again (this can take several hundred to a thousand years) in the the rest...
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Thanks for your question @VoskehatIsakhanyan and for great answers @DianaM
Thinking maybe also this comment refers to tides - the Moon and the Sun (not as much the planets) impact the tides on Earth, this is not the same as ocean current though.
For the atmosphere, there are also tides, but these are negligible compared to weather and the large scale...
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Thanks @GeoffPhillips - a very nice and short summary!
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Kerim Hestnes Nisancioglu replied to [Learner left FutureLearn]
Dear @LorraineP don't worry, you are not the only one challenged by the exercises. We recommend that you watch the videos, read the following article and complete the quiz + you will get input form your peers as well as us along the way. Next week is on climate feedbacks (how small changes in radiative forcing are amplified giving larger changes in climate),...
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Thanks, we are aware that this topic is quite challenging. This is also true for the details of the greenhouse effect in the next lecture. However, we very much recommend looking at the first two links in the recommended reading sections for clarity. Also, it is totally fine just to see the videos, but we recommend completing the quiz (based on video and...
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Based on your questions and interactions we will decide what to discuss during our weekly feedback sessions. These will be posted as a video at the end of each week.
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Hi Geoff. Thanks for your questions. We will try to answer this during our Friday feedback video - will be available later today. If not we will answer you directly here.
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Hi zainah, cool that you joined the course. We recommend stating seeing the videos and doing the quiz - some of the articles and excises will be quit tough. But hope you will make the most of it anyway!
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Great to have you Fifi - we are building a new curriculum on the sustainable development goals here in Bergen. So far we have 4-5 dedicated course, including one by me and Asgeir on SDG13 Climate Action. Hoping to make it available online soon.
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Cool to have you onboard :-) one of the best lectures on ocean currents I have experienced was by a sailor on our tall ship Statsraad Lehmkuhl from Bergen.
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Hi Lisa - we are working on making a similar course adapted to teachers needs - so any input is most welcome.
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Bergen and the fjords is a must if you find time to visit Norway!
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Dear all, for more examples of natural radiative forcing and the role of changes in the Earth's orbit I recommend checking out the video from the Khan Academy in the "Recommended Reading" section. There is also a great overview by NASA here: https://climate.nasa.gov/news/2948/milankovitch-orbital-cycles-and-their-role-in-earths-climate/
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Dear all, we recommend you read the additional material here before completing the exercises in the next step. However, if you only want to learn the basics you can watch the video, read the article and do the quiz (and skip the recommend reading and exercises - but again, better to complete all steps!).
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Thanks Christophe. This topic is indeed challenging, as suggested here we very much recommend the Khan academy videos for additional study.
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Dear all - thanks for your questions! Please have a go at answering each others questions - then if unclear we (the educators) will join-in and clarify.
The best learning experiences comes from an active discussion!
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Never too old to learn something new! Great to have you Richard. Would appreciate your input on historical aspects relating to climate change and how our perception has changed through time.
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Hi Philip great to have you onboard. We have a an active community of geoscience, physics and maths teachers from Norway who have followed this course over the past few years. Any input on what is relevant for you as a teacher is very welcome.
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Glad to have you Jacqueline. Would be great if you share syour knowledge on disaster management during the course discussion. We are working on adding a module on the impacts of climate change to this course - currently this is only offered offline as a traditional course at the University of Bergen.
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Thanks for sharing Richard - tipping points and ice melt are one of the topics we will come back to and discuss during the course.
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PS! We are also working on a short version in Norwegian of our course for for school teachers. Will see if we find a good collaborator given that there is an interest in a German version.
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Kerim Hestnes Nisancioglu made a comment
Very happy to see so many of you joining our course - we only decided very recently to rerun this course an extra time this spring given the closing of traditional classroom teaching at our University here in Bergen.
I am Kerim and the lead educator for this course, together with Asgeir Sorteberg we developed our course over the past 5 years. I am a...
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Kerim Hestnes Nisancioglu made a comment
Dear all, given the situation in many countries with universities and work places closing down due to the COVID-19 pandemic we decided to put on this extra run of our climate MOOC.
Looking forward to following you thru the course over the next 3-4 weeks together with Asgeir, Anais and Jonathan from the University of Bergen.
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Great to have you back Ailin!
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Kerim Hestnes Nisancioglu replied to sandra c-f
Hi @sandrac-f , you will find the new feedback videos appearing at the end of each week - by mistake last years video was posted as placeholder. This has now been removed. Please see video at end of week 1 as well - on Amazon rainforest fires.
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Kerim Hestnes Nisancioglu made a comment
The feedback video for this week will appear on Friday.
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Kerim Hestnes Nisancioglu made a comment
Dear all, thanks for following our course. We realize that some of the material is challenging for many of you. If this is the case we recommend that you see the videos, do the quizzes and read the article we provide for each topic. The additional reading and exercises require more work and can be left out - you can still follow week 2 and 3.
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Kerim Hestnes Nisancioglu made a comment
Dear all. Welcome to our course and greetings from Norway!
This year there will be a group of about 35 students following the course together with you from the University of Bergen. We, the educators (Kerim, Asgeir, Mari and Anais), will be meeting with them twice a week in class to follow up the course and hope to continue the many discussions with you... -
Thanks for the questions and insights. We have not covered ocean acidification in this course, but one important impact of higher CO2 in the atmosphere and concurrent uptake and dissolution in the Ocean is higher Ph and acidification of the ocean. This is of grave concern as many organisms with calcareous structures will be affected.
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Yes! Thanks Steve. Need combination of increased volcanic activity and reduced sunspot activity.
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Dear all, thank you for your efforts so far. Keep up the good work! We are very much aware that this exercise is challenging and do not expect everyone to complete this part. You can follow the course also without completing all the exercises using the climate model provided.
This hands-on component will secure a deeper understanding of the topics, but the...
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Sunspot activity can cause changes in climate on earth and is likely to have caused the little ice age. However, it is important to note that the little ice age was a regional cooling mostly seen in the Northern Hemisphere and in particular over Europe, so it was probably not a response to the Maunder minimum alone.
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Thanks for the good discussion. We normally talk about glacials and glacial cycles when referring to the times when large areas of the North American and Eurasian continents were covered with ice caps. The last glacial cycle lasted from about 80,000 years to 20,000 years ago with the last remnants of the large ice caps disappearing by about 10,000 years...
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Thanks Peter, we will elaborate on this topic in the end of week 2 feedback video.
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Nice point Ian. The impact of ocean temperature will be less on land masses further downstream from the North Atlantic. The strongest impact is felt on west coast of Europe, and much less as you move inland to e.g. Russia, where the weather is more continental with large seasonal contrast in temperature. This is because the ocean not only warms adjacent land...
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Thanks for your comments. The "cold blob" seen in the North Atlantic, and more specifically in the Irminger Sea, has been a matter of debate over the past years. Some view this as a slowing of the meridional overturning circulation in the Atlantic (the AMOC) which brings warm water north leading to relatively warm ocean temperatures in the North Atlantic (you...
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Good point. Yes, CO2 will equilibrate over time. However, during the past there have been long periods with increased volcanic activity. This would have changed the equilibrium level of CO2 in the atmosphere and sustained it for longer periods of time.
For a description of the lifetime of CO2 in the atmosphere see this...
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Thanks for your questions! If the Gulf Stream were to weaken, less heat would be transported from the South Atlantic to the North Atlantic. In this case the North Atlantic (and northern Europe including Norway) would experience a cooling, while the South Atlantic would experience a slight warming. However, this impact is smaller than the general increase in...
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The mild climate of western Europe is caused by a combination of warm surface ocean temperatures off the coast, and the prevailing westerly winds transporting heat from the ocean to the European continent. This transfer of heat from ocean to land comes in addition to the large scale transport of heat by the atmosphere and ocean from the tropics to the polar...
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It is likely that the Gulf Stream has been in existence since the opening of the North Atlantic, which started about 100 million years ago. This is because the Gulf Stream is part of the wind driven circulation of the ocean, and as long as we have winds (which we always had) there will have been a Gulf Stream, or at least a similar circulation in the ocean...
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Thanks Louis, both for the encouragement and the great link. Had not seen this before. Gives a good overview of natural versus man-made forcing over the past 100+ years!
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Kerim Hestnes Nisancioglu made a comment
Dear all, thanks for all your great comments and questions. You will now also find a transcript attached to the feedback video of week 1 above.
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There has been a lot of discussion in the literature relating to the impact of freshwater forcing on the stratification of the North Atlantic. If sufficient freshwater is present, the surface ocean will become very light and could prevent the production and sinking of deep water in the high latitudes.
Today this deep water production is part of what is...
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Thanks for your comment. This is an important point. The Gulf Stream (and its extension into the Nordic Seas) alone does not heat the European continent. It is rather the combination of the anomalously warm ocean surface off Europe and the prevailing westerly winds which give rise to the relatively mild climate of Europe. This is noted in the video and in the...
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Thanks for spotting this. Yes, indeed, in the Atlantic, the northward flowing western boundary current originating in the tropics (which includes the Gulf Stream) is balanced by a southward recirculation surface current in the eastern part of the basin (this has been corrected).
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Thanks for your questions and comments. After a volcanic eruption the sulphate aerosols (which have a cooling effect on climate) will fall out and the impact on climate will be insignificant after a few years, depending on the size of the eruption. In terms of CO2 emissions, most volcanic eruptions of the recent past have been insignificant, in particular when...
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The Eyjafjallajökull eruption in 2010 did not cause any significant change in climate. However, it did impact local farmers and residents on Iceland due to the fallout of ash as well as a large jökulhlaup - these is a flood caused by meltwater from the glacier covering the volcano. However, historically volcanic eruptions on Iceland, such as the Laki eruption...
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This is an interesting topic indeed. The end Permian extinction is thought to have been caused by massive volcanic eruptions (known as the Siberian traps) and emissions of vast amounts of gases to the atmosphere. The reason for the extinctions were most likely due to a combination of global warming and ozone depletion following the event. For other mass...
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This is a good question! There are few if any natural sources which can match the present man-made emissions of CO2 to the atmosphere - in particular when you consider the rapid rate of increase we have experienced the last 150 years. A few of the natural factors impacting the atmospheric concentration of CO2 include weathering of silicate rocks, sedimentation...
