Greenwashing’s new distant cousin

by Clara Nack

“Act Responsibly Even when You Don’t.” Next to this ambiguous slogan, two young models in jeans are lolling about, promoting Diesel’s Green Label, the brands’ sustainable line. And this is what follows: “Go crazy and at the same time treat the planet with our responsible pieces from the Fall Winter 2020 collection”. Sustainability and shopping the new arrivals of each and every season – how “consciously” and “responsibly” sourced they may be – does that match? On another rather urgent note: I still needed Christmas presents when I read this.

Screenshot Diesel Jeans

Googling “sustainable gifts” will return all sorts of attractive results that labels have not only given the Christmas coat of paint, but also a supposedly green one. And in 2020, sustainability as an incentive to buy has had other suits made to measure. There is the #supportyourlocals hashtag, with which online retailers such as Amazon and Zalando are luring me to buy, buy, buy and feel good about it. It’s Christmas after all and everyone should share a piece of the cake. Continue reading Greenwashing’s new distant cousin

Negative emissions – a key assumption in limiting temperature rise

by Ella Karnik Hinks

The application of “negative emissions” technology has been widely used by the IPCC and incorporated into models which predict the most modest estimates of limiting the global temperature rise to 2 degrees [2]. Bioenergy and Carbon Capture and Storage, commonly known under the acronym BECCS, is one such technology. In principle, it works by using biomass as an energy source, and then capturing and storing the carbon dioxide release associated with this process.

Bioenergy and Carbon Capture and Storage infographic
Bioenergy and Carbon Capture and Storage – infographic by Ella Karnik Hinks

Using bioenergy as a fuel is not a new concept – for example burning wood or waste agricultural products, such as sugar cane. So far so good.

However, “negative” emissions are only achieved if the amount of carbon dioxide subsequently stored is greater than is emitted during the biomass production, transportation and utilisation [1]. Theoretically, CO2 can be stored by pumping it underground into geological formations. Yet there remains, in practice, a big “if”, when looking at the current existing facilities of carbon capture and storage – the two processes (of BE and CCS) currently only operate in one commercial plant in the United States [3].

Fundamentally, the issue with the inclusion of such technologies into IPCC models is two-fold: Continue reading Negative emissions – a key assumption in limiting temperature rise

Kein Fortschritt ohne Risiko

von Joana Kollert 

Neulich bin ich zum ersten Mal in einem autonomen Fahrzeug gefahren. Das HOCHBAHN-Forschungsprojekt HEAT testet die Eignung des ersten automatisiert fahrenden Kleinbusses im Hamburger Straßenverkehr. Jede*r kann sich die HEAT-App herunterladen und kostenlos mitfahren. Die Vorstellung, im unbemannten Kleinbus durch die Hamburger HafenCity zu cruisen fand ich aufregend und ein wenig beängstigend. Die Realität war aber harmlos und reichlich unspektakulärer: gemeinsam mit zwei HOCHBAHN Angestellten und einem weiteren Fahrgast tuckelten wir gemächlich über eine Strecke von 800m, von denen wir nur die ersten 100m autonom fuhren, bevor ein Falschparker die manuelle Übernahme erzwang.

Der HEAT Kleinbus in der Hamburger Hafenctiy.

Continue reading Kein Fortschritt ohne Risiko

Planting trees to save the climate?

by Susan Jörges

„We plant one tree per product”, an organic chocolate bite company claims that cooperates with Eden Reforestation Projects. “With your help we have already planted 15.000 trees in Columbia”, is written on the website of a company that sells organic cosmetic products in recyclable glass bottles. Planting trees for every product sold seems to be fashionable. Product variety is expanding on all markets, and consumers are becoming more critical.  But is planting trees an effective solution for preventing climate change? Is climate change mitigation that easy?

sapling on the palm of a hand, picture by pexels

Continue reading Planting trees to save the climate?

2019 on Twitter: Climate activism awakening

by Hadas Emma Kedar and Fenja De Silva-Schmidt

Shortly before 2020 is over, we will have a look back at 2019 to map the climate change debate as reflected transnationally on Twitter. Compared with the two years prior, 2019 showed a particular abundance of climate-related tweets: While the total tweets count of 2018 grew by 8% from 2017, the total count of 2019 grew by 70%. Then what triggered the climate discourse so much on Twitter that year? Continue reading 2019 on Twitter: Climate activism awakening

Overstimulated by the news: How to navigate through times of crisis

by Susan Jörges

“Robert-Koch-Institute reports highest daily number of infections”, appears on the screen of my phone. The local newspaper lying on the kitchen table is titled with a similar headline, corona is issue number one in the evening TV-news, and my Instagram feed recommends a livestream of the government´s press conference.

Photo from

Continue reading Overstimulated by the news: How to navigate through times of crisis

How to talk about climate change – a collection of thoughts and helpful input for non-experts

by Fenja De Silva-Schmidt

When did you talk about climate change the last time? And when did you do so with family and friends? Results from our surveys show that on the one hand, the amount of people talking about climate change in their daily lives is rising steadily (see Guenther et al. 2020, in German), but on the other hand, a significant share of people never touch the topic in their conversations. For many, it is a somewhat awkward topic, leading to conversations about guilt and depressing visions for our future.

Rising share of conversations about climate change in daily life, source: Down to Earth data 2015/2019.

rising share of climate change conversations 2015-2019

In this post, I’ll summarize why it is a good idea to talk about climate change, even if you are not a climate expert, and which strategies mostly lead to a constructive conversation. Continue reading How to talk about climate change – a collection of thoughts and helpful input for non-experts

Addressing the Nation: Pandemic!

How was the Covid-19 pandemic communicated by different leaders in their televised speeches and why does it matter?

by Hadas Emma Kedar

Illustration: screenshots of speeches of world leaders (between 16.-26.03.2020) [different online sources].
Six months have passed since nations of the world have locked-down against the spread of Covid-19. After its classification as a pandemic by the World Health Organization on 11 March 2020, leaders have addressed their nations to declare an emergency. These “addressing the nation” speeches are worth examining, as they deal with the same crisis at the same point of time, and it seems fair to assert that a great deal of a society’s behavior stems from its leader’s public expressions. For example, terms like war, enemy or discipline might encourage anxiety and violence among citizens, while challenge, strength and solidarity might encourage emotional strength and decrease anxiety.

Continue reading Addressing the Nation: Pandemic!

What is a Climate Model?

by Felix Schaumann

Last August, our blogger Shorouk Elkobros explained what a climate model is in this video. One year later, climate models are still an essential tool for understanding global warming. In order to remind us how climate models work, Felix Schaumann has put together his own explanatory video.

Continue reading What is a Climate Model?

After Lunch Posts: Talking Climate Change with Hans von Storch

by Michael Brüggemann

One of the many privileges of holding a Professorship at the University of Hamburg and being involved in the Cluster of Excellence, which unites researchers from different disciplines around the issue of climate change (see CLICCS website ), is that you have the opportunity to meet and have lunch with highly inspiring and thought-provoking people such as Hans von Storch.

Hans von Storch captured by Raimond Spekking (via Wikimedia Commons)

Continue reading After Lunch Posts: Talking Climate Change with Hans von Storch