calving iceberg

Project: Wave propagation and radiative transfer in the atmosphere

Wave propagation and radiative transfer in the atmosphere is a modern research area with immediate connection to the greenhouse effect and the global warming. The long term goal of the project is to contribute to more accurate predictions and an increased knowledge of the field.

Project information

Project name
Wave propagation and radiative transfer in the atmosphere, the greenhouse effect and global warming
Project manager
Sven Nordebo
Other project members
Christian Engström, Linnaeus University; Pieter Tans, NOAA Global Monitoring Laboratory, USA
Linnaeus University
Electrical engineering (Department of Physics and Electrical Engineering, Faculty of Technology)

More about the project

The topic of wave propagation and radiative transfer in the atmosphere, the greenhouse effect and global warming is a timely subject area embracing many scientific and technological advancements and challenges. Not only does it provide a basic understanding of the physical principles underlying the climate changes, it also provides a unifying interdisciplinary theme connecting many interesting research areas within the natural and technological sciences. Some of these are Earth and environmental sciences, chemistry, physics, electrical engineering and applied mathematics.

The research project is addressing the following specific areas:

1) Statistical analysis of climate data and short-term global trends

Nowadays, the amount of greenhouse gases as well as mean surface temperatures are routinely measured around the world. This provides an irreplaceable source of data, information and analyses as a basis for policymakers in their quest to mitigate the global warming. It is therefore of utmost importance to understand precisely the variability and accuracy in these measurements in order to make correct interpretations of the data.

Our research is aiming to develop new tools based on estimation and statistical theory to provide analysis and validation of short-term global trends in the abundance of the atmospheric greenhouse gases and other climate related data.

2) Radiative transfer and quantitative spectroscopy

The theory of radiative transfer in the atmosphere is an important tool for being able to predict the greenhouse effect, the radiation budget of the planet and the global warming in different scenarios. Quantitative spectroscopy is in the core of the radiative transfer calculations and constitute a modern research field with many recent results of great importance. Today, researchers are speaking about spectral profiles "beyond Voigt" (i.e., beyond the classical spectral profiles) and are continuously trying to improve and implement new spectroscopic models, e.g., by taking into account line mixing and velocity changes due to molecular collisions.

Our research is aiming to analyze and refine these models by taking into consideration the fundamental mathematical and physical properties relating to passivity, positive real (or Herglotz) functions and the associated optical theorems and sum rules. The research is also aiming to develop more efficient numerical implementations of advanced spectral profiles in computer programs that are based on "line-by-line" calculations.

The project is part of the research in the Waves, Signals and Systems research group.

Example of an atmospheric model

Explanation of the model above

The video above is also explained in Sven Nordebo's recent talk The greenhouse effect, radiative transfer in the atmosphere and quantum mechanics, recorded at the conference Quantum Information and Probability: From Foundations to Engineering (QIP) held August 25–27, 2021 at Linnaeus University. You can also download the presentation from the talk (pdf file).