Real climate science – uncertainty and risk

As we enter the mid-2020s, public discourse and government policy in rich nations focus intensively on climate. The idea that we live in a time of “climate crisis” garners more and more attention, fueled by publicity around every bad weather event and dire pronouncements of ever-more intense and frequent storms, floods, droughts, and other calamities to come.

Greenhouse gas (GHG) emissions from human activities – primarily carbon dioxide (CO₂) and methane (CH₄) – are blamed by many for accelerated climate change and the aforementioned crisis. Transitioning energy sources away from fossil fuels – oil, natural gas, and coal – to low-emissions alternatives is championed as humanity’s only chance to “stop climate change” and “save the planet”. International agencies such as the United Nations and International Energy Agency (IEA) lead the way in setting goals such as “net zero” emissions by 2050 to forestall the crises.

You may notice that I place quotation marks around dramatic catch phrases such as “climate crisis” – phrases designed not to inform but to communicate the gravity and overwhelming importance of this world view. Perhaps the most important catch phrase is “The Science”, which serves as the primary justification for the crisis movement.

The Science references the “settled science” of climate analysis and modeling, which apparently proves that anthropogenic (human-made) GHG emissions are causing the planet to heat up, resulting in entirely negative weather outcomes – more storms, more floods, more droughts, failed crops, population centres rendered uninhabitable … the list goes on.

Yet the loudest proponents of climate crisis and doom – UN Secretary-General Antonio Guterres, former U.S. vice-president Al Gore, Swedish activist Greta Thunberg, and Canada’s own Minister of Environment and Climate Change Steven Guibeault – have no scientific training, and exhibit no signs of understanding the nature of scientific investigation and discovery. For them, The Science is promotion of specific talking points, not actual science.

Real climate science

So what is “real” climate science?

First, the term “climate science” is a relatively recent invention, most commonly referenced by non-scientists. The actual scientific disciplines are meteorology (the study of the atmosphere and its effects on weather) and atmospheric physics (the study of fluid flows, radiation budgets, and energy transfer processes in the atmosphere). Scientists engaged in these disciplines seek to understand the behaviours of Earth’s atmosphere and linked systems, such as the oceans. Most of their work addresses specific scientific questions, such as these papers from recent scientific journals:

• • “Increase in Madden-Julian Oscillation (MJO) predictability under global warming” (Nature Climate Change)

• • “Reservoir CO₂ and CH₄ emissions and their climate impact over the period 1900-2060 (Nature Geoscience)

Such highly arcane (at least to the general public) studies are the foundations of climate science, building understanding of particular aspects of complex atmospheric systems and the factors that control them.

But “climate science” in popular media generally references global climate models – computer simulations of Earth systems – that can be used to model future climate trends and weather patterns. They are viewed by many, particularly proponents of the “climate crisis”, as definitive predictions of what climate and weather changes will occur in the future, particularly in response to anthropogenic influences.

Real climate, climate-related sciences, and climate forecasting are not that simple. For a real-world understanding of climate and climate science, I turn to Dr. Judith Curry’s recent book “Climate Uncertainty and Risk – Rethinking our Response”.

Dr. Curry holds a PhD in geophysical sciences, and is a professor emeritus and former chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology. Her academic research focused on hurricane controls, and she serves as president in the private-sector Climate Forecast Applications Network. Her book is a heavy read – full of facts, references, and deep analysis, much like Vaclav Smil’s definitive works on energy and world systems. Scientific laypeople will find it a struggle, and Dr. Curry herself agreed with me on LinkedIn that it needs “translation” to be understood by the general public.

The translation

So what does Curry tell us about climate science that people need to understand in order to have a more accurate view of climate, how it might change in the future, and what needs to be done about it? Some key points:

1. Climate systems are complex. Behaviours of the atmosphere and ocean, and feedbacks between various subsystems are not well understood, and can only be approximated by equations and numerical models. Climate science today cannot tell us:

• • Whether human-caused emissions have dominated over natural climate variability as a cause of recent warming
  • How much the climate can be expected to change over the 21st century
  • Whether warming is dangerous
  • Whether radically reducing emissions will improve human well-being

Climate is, indeed, very complex. In other words, it is a “wicked” problem, not given to simple or linear approaches or solutions.

2. A consensus of scientists “represents a deliberate expression of collective judgment by a scientific institution or group of scientists, often at the official request of a government or other organization.” Any such consensus is not evidence for or against a particular idea or hypothesis.It does not matter who is for or against a particular scientific concept. Only the facts matter, not endorsements.
3. Skepticism is the foundation of science, and scientific skepticism is about protecting the integrity of the scientific process.Good scientists ask questions and seek to improve the science. Asking questions and raising valid counterpoints is fundamental science. Yet crisis proponents often characterize important questions as “denial” of the “settled science”.
4. There are many uncertainties associated with our understanding of climate. Curry defines uncertainty as “a state of incomplete knowledge arising from a lack of knowledge or from disagreement about what is known or even knowable.” She goes on to say that “the fundamental mischaracterization of climate change as a tame rather than a wicked [complex] problem has resulted in institutionalized efforts to ignore, simplify, reduce, and control uncertainty.”In other words – there have been systematic efforts made to present the results of climate models and dire predictions of global warming as reliable, without acknowledging our lack of knowledge and uncertainties about what models are actually telling us.
5. Global climate models (GCMs) “represent aspects of climate that are difficult to observe, experiment with theories by enabling otherwise infeasible calculations, understand a complex series of equations that would otherwise be impenetrable, and explore the climate system to identify unexpected outcomes.”They are used to “assess the causes of recent climate change, predict future climate states, provide guidance for emissions-reduction policies, support local adaptation policies, and to provide inputs for integrated assessment models to assess the social cost of carbon.”All great principles – but Curry takes 12 pages after these defining statements to address the inadequacies of GCMs in addressing climate chaos and uncertainty, the difficulties of model calibration and tuning, the variety of modeling techniques, inadequacies and uncertainties inherent in all climate models, and finally to address the fundamental question – can we have sufficient certainty in climate models to serve as useful foundations for prediction of future events?

   Anyone familiar with numerical modeling of complex physical systems (e.g., modeling of fluid flow in subsurface reservoirs) will likely understand and agree with Curry’s conclusion that “the adequacy of climate models for the purpose of predicting future climate is particularly difficult and arguably impossible.” She provides a particularly telling quote from mathematician Andrea Saltelli:

• • “Mathematical models are a great way to explore questions. They are also a dangerous way to assert answers.”

Why is real climate science important?

“Climate science” – primarily atmospheric physics and meteorology – encompasses study of highly complex, chaotic systems that we struggle to understand. Findings and models are laden with uncertainties, and wildly different scenarios can be envisaged using different assumptions and inputs to global climate models.

Representations of this complexity as “settled science” and forecasts of future climate as definitive are simply wrong and highly misleading. That is not how complex systems with millions of variables and unpredictable interactions work.

I have written a lot about energy in today’s world, and how it is fundamental to human prosperity and wellbeing. Access to abundant, affordable, and reliable energy is arguably the most important issue facing humanity today. But energy is inextricably linked to climate, as we create more than 80% of the energy we use by burning fossil fuels, which create GHG emissions.

The future of all humanity rests on good policy decisions by our leaders, steering our actions in the best directions to achieve success and prosperity for all. Policy decisions must incorporate many high-quality inputs including social, political, and economic factors. Perhaps most important, they must be supported by solid, realistic science representing our best, most accurate research and understanding.

But fundamental misunderstanding and over-simplification of climate science has elevated “climate crisis” scenarios to highly influential policy inputs. Instead of prioritizing adequate, affordable energy for all eight billion human beings on this planet, policy in many rich nations focuses on arbitrary targets to reduce GHG emissions with scant regard for energy security or financial, social, and other environmental issues.

Employing real climate science will support decisions to create more balanced policy and a better future for every human being on Earth.