CR
Cryospheric Sciences

CO2 emissions

It’s getting hot in here: Ancient microbes in thawing permafrost

October 22, 2021
It’s getting hot in here: Ancient microbes in thawing permafrost
Figure 1: You wondered what can live in frozen, ancient soil? Here you can see intact (A) and thawing permafrost (B). While Bacilli (red) and spore formers (green) can survive in the frozen and thawed permafrost, other species, such as Actinobacteria (blue) do not like it too much when it thaws. Carbon gets digested into carbon dioxide (CO2) and methane (CH4), of which most is released into the atmosphere. Little is known about fungi (light brown) but they do exist. [Credit: Maria Scheel, created with biorender.com]

Did you know that the oldest organism on Earth is believed to be a microorganism found in 3-million-year-old permafrost in Siberia? There, it was living at a cosy average temperature of -10 °C at 14 m depth. Or did you hear that some other Arctic soil microorganisms can happily live at extreme temperatures down to -40 °C? Scientists often use these “extreme” microorganisms to get an idea on how ex ...[Read More]

The future of Arctic sea ice

July 10, 2020
The future of Arctic sea ice
Figure 1: Sketch that shows the presence (in white, ‘ice covered’) and absence (in blue, ‘ice free’, i.e. less than 1 million km2 of sea ice) of Arctic sea ice for different levels of warming (X axis) and the different months of the year (Y axis), based on the extrapolation of observations. The estimated warming in 2018 is marked with ‘today’. Figure credit: Fig. 1 of Notz and Stroeve (2018).

The illustration above shows a sketch of the evolution of Arctic sea ice for different levels of warming and the different months of the year, based on the simple extrapolation of observations. A new study, in which I was involved, uses the latest available global climate models and shows that the Arctic Ocean could become practically ice free at the end of the summer for the first time before 205 ...[Read More]

Image of the week – Learning from our past!

September 1, 2017
Image of the week – Learning from our past!
Figure 1: Peak global mean temperature, atmospheric CO2, maximum global mean sea level (GMSL) and source(s) of meltwater over the past 3 million years. The light blue area on each bar indicates the uncertainty associated with the maximum global mean sea level , and the pie charts denote the fraction (not location) of ice retreat in Greenland and Antarctica [Credit: Dutton et al. (2015)].

Understanding the climate evolution of our planet is not an easy task, but it is essential to understand the past if we are to predict the future! Historic climate cycles provide us with a glimpse into a period of time when the Earth was warmer than it was today. Our image of the week looks at these warmer periods of time to see what they can tell us about the future! For example, during the Plioc ...[Read More]

Image of the Week – For each tonne of CO2 emitted, Arctic sea ice shrinks by 3m² in summer

January 20, 2017
Image of the Week – For each tonne of CO2 emitted, Arctic sea ice shrinks by 3m² in summer
Mean area of Arctic September sea ice lost by CO2 emissions of each citizen for each country of the world in 2013. These results are based on the observed trend of 3 m² sea-ice area loss per tonne of CO2 emitted [Credit: adapted from Notz and Stroeve (2016), Fig.S1]

Declining sea ice in the Arctic is definitely one of the most iconic consequences of climate change. In a study recently published in Science, Dirk Notz and Julienne Stroeve find a linear relationship between carbon dioxide (CO2) emissions and loss of Arctic sea-ice area in summer. Our image of this week is based on these results and shows the area of September Arctic sea ice lost per inhabitant d ...[Read More]