CR
Cryospheric Sciences

For Dummies

Recipe to quantify calibration errors in a time-dependent ice sheet model

October 27, 2023
Recipe to quantify calibration errors in a time-dependent ice sheet model
Figure 1: Upper diagram: schematics of baking a pie, representing an idealized 1D Bayesian inverse problem. Lower diagram: schematics of a multi-dimension ice sheet inverse problem solved using FEniCS_ice error propagation framework, created from a compilation of figures from Recinos et al. (2023). FEniCS_ice is designed to solve these problems over a finite element mesh containing (in this study case) more than 100,000 elements. These elements are the vertices, faces, and edges that form our triangular mesh (red map, check out ingredients list below for more information). [Credits: Beatriz Recinos, baking icons from https://www.flaticon.com/].

Ice sheet models are awesome tools that help us learn and predict the fate of ice sheets under human-induced climate change. However, all models have errors. What types of uncertainties exist in an ice sheet model and how can we quantify some of them efficiently? Check out our recipe to quantify one type of uncertainty in sea level rise projections: The model calibration error. Not a numerical mod ...[Read More]

For Dummies: Radar altimetry for measuring ice sheet elevation changes

March 3, 2023
For Dummies: Radar altimetry for measuring ice sheet elevation changes
Greenland and Antarctica surface elevation changes from CryoSat-2. Credit: ESA, Inès Otosaka.

Does measuring the surface of the ice sheets provide more than superficial knowledge of their current status? Read further to find out why the answer is definitely yes! Measuring surface elevation changes actually tells us where Greenland and Antarctica are thinning or thickening and how much they contribute to sea level rise. Scientists have been doing this for the past three decades, so keep on ...[Read More]

For Dummies: How Arctic sea ice and the AMOC interact

December 9, 2022
For Dummies: How Arctic sea ice and the AMOC interact

In this post, I will talk about two famous characters of the climate system; I will define them and see how they have changed in the current context of climate change. I will also show you how these two characters interact, one influencing the other, and vice versa. Finally, let’s see how the future looks like for them and the consequences for the global climate. I hope you will enjoy this story. ...[Read More]

phase-sensitive Radio Echo Sounder, a.k.a. pRES, For Dummies

September 30, 2022
phase-sensitive Radio Echo Sounder, a.k.a. pRES, For Dummies
Figure 1. pRES with four antennas mounted behind an autonomous ice rover to collect polarimetric radar data over the Ekström ice shelf - Antarctica (ReMeltRadar2021-22). Photo credit: Reza Ershadi.

Greetings! My name is Reza. I’m (still) A PhD candidate in Geophysics and Glaciology at the University of Tübingen in Germany. Today, I will tell you all about a device named pRES, a radar system designed to study ice. Well, pRES and I have had an immense love/hate relationship during the last four years. It is one of the main tools I have used during my PhD, working in the Alps and Antarctica. I ...[Read More]

Subglacial Hydrology For Dummies – Water, water everywhere…

February 19, 2021

Glaciers are mostly made of water. Sometimes, perhaps more than we’d like, some of that water makes a break for it by melting, the inconstant molecule… It might pootle around on the surface of the glacier a bit and get a lot of remote sensers very excited, but it’s what it does once it gets to the base of the glacier that really matters for the behaviour and flow of the ice. So, in 2000 word ...[Read More]

Hysteresis For Dummies – Why history matters

December 4, 2020
Hysteresis For Dummies – Why history matters
Simple illustration of the concept of multi-stability and tipping points of an ice sheet: the stability of the large Antarctic Ice Sheet can be seen as a seesaw. It starts off stable on the left side, but as temperatures rise, the ice starts to melt and lose mass, resulting in the left side of the seesaw getting progressively lighter. Up to a certain threshold, the seesaw remains stuck in its initial position, but upon transgressing the critical threshold, the system flips over, the seesaw switches into the right state which is associated with a much smaller ice sheet. Figure credit: J. Garbe.

Perhaps you have stumbled upon the word ‘hysteresis’ before, for example in connection with the stability behavior of our Earth’s large ice sheets and their long-term effect on global sea-level rise, or the long-term stability of the Atlantic Meridional Overturning Circulation, or even in another context outside earth/climate science. Or you might have come across this term during your studies, bu ...[Read More]

How small changes can make a big difference: tipping points in Antarctica

November 13, 2020

As Antarctica’s mass loss increases, the threat of crossing tipping points both in the ice sheet and the surrounding Southern Ocean is increasing. But what actually is a tipping point? Have tipping points already been crossed in the past? And what might the future hold? What do we mean by a “tipping point”? Scientifically speaking, a tipping point is generally understood to be a threshold that, on ...[Read More]

For dummies – About ice sheet models and their cold relationship to climate models

April 17, 2020

Climate models help us understand processes occurring in and between atmosphere, oceans, land and ice-covered regions of our planet. One important process impacting all of us is sea level rise, and the ice sheets of Antarctica and Greenland (currently losing more and more ice) play a crucial role in future sea level rise projections. Even though climate models can be very complex and include many ...[Read More]

For Dummies – How do wildfires impact permafrost? [OR.. a story of ice and fire]

November 1, 2019

Wildfire – like the ones observed in the Northwest Territories, Canada in 2014 (Fig. 1) – is a natural part of permafrost landscapes, but fires are expected to get more frequent and severe as the climate warms. This could accelerate the degradation of permafrost, with negative consequences on the local and global scale! We have a pretty good understanding of how permafrost responds to fire t ...[Read More]

Ice Cores “For Dummies”

December 14, 2016
Ice Cores “For Dummies”

Ice cores are important tools for investigating past climate as they are effectively a continuous record of snowfall, which preserves historical information about climate conditions and atmospheric gas composition. In this new “For Dummies” post, we discuss the history and importance of ice-core science, and look at the way we can use ice core chemistry to reconstruct past climate. Ice sheets, arc ...[Read More]