ENG - Cambio Climatico y Sostenibilidad - TEC_TEMPLATE_RUTA_AZUL-2

Climate change basics: science and impacts

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IPCC, working groups and key messages

Climate change: civilizational or environmental problem?

Basic concepts

Basic concepts

Sustainability: polar bears or existential threat?

What do you imagine when you hear "climate change?

What do you think when you hear "sustainability?

Polar bears, hippies or a matter of philanthropy?

Or is it an existential threat?

What conceptual differences should we pay attention to?

Weather

Climate

Global warming vs climate change

Effects vs impacts

Climate change: civilizational or environmental problem?

Climate change: civilization or environmental problem?

Natural forces

Human activity

How long have we known about climate change, and what adversities has climate science encountered?

Hansen vs. Senate Committee

Science Advisory Commitee

Arrhenius

On June 23, 1988, James Hensen gave a statement before the Senate Committee on Natural Resources Energy where he argued...

Considered the father of climate science, he made the first calculation of global warming due to human CO2 emissions

In 1965, President Lyndon B. Johnson (USA) received a report by SAC linking human activities to climate change

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IPCC, working groups and key messages

Creation of the IPCC

What is the IPCC and what is its purpose?

How does the IPCC operate?

Is the IPCC political?

How is the IPCC organized?

Current reports

Key Messages from Working Group I: Physical Basis of Climate Change

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Human activity

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crossing 1.5º C

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intensified climate change

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emissions

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Key messages from Working Group II: Impacts, Adaptation and Vulnerability

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impacts and risks

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Risk analysis

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chain risks

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adaptation

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Climate change impacts in México

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México and climate change

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Climate impacts

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DAMAGE ANALYSIS

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ECONOMIC IMPACTS

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Key Messages from Working Group III: Climate Change Mitigation

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Limiting heating

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From agreements to actions

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CAT PROJECTIONS

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NET EMISSIONS

The course is set

"Climate change is already here. It's frightening. And it's only the beginning. It is still possible to limit global temperature rise to 1.5°C (above pre-industrial levels), and avoid the worst of climate change. But only with drastic and immediate climate action." Antonio Guterres, 27 July 2023.

Questions? Contact us: contactorutaazul@servicios.tec.mx

Chain reaction and systemic connections

As we can see, the climate crisis generates multi-sectoral chain reactions (click on the image to enlarge).

This is why systems thinking will help us to identify the connections between existing risks. With this way of thinking we will also be able to anticipate effects and impacts with the application of measures. Check out this example from the Global Risks Report on pages 8-10 to see how it helps us to understand the complexity of the risks we face.

(Zhang, 2011)

● The cumulative costs during this century would be comparable to losing between 50% and up to more than 4.5 times Mexico's current GDP. ● In the second part of the century, most of Mexico would have annual losses equal to or greater than 5% of local GDP due to climate change. ● Annual temperature increases of more than 4ºC could be reached during the 2070s in parts of Mexico. ● Ecosystems would be unlikely to adapt to this change. ● Mexico City, Guadalajara and Monterrey: climate change losses could exceed US$1 billion in the 2020s. Source: Estrada, F. Botzen, JW (2021) “Economic impacts and risks of climate change under failure and success of the Paris Agreement”

What is the IPCC?

The Intergovernmental Panel on Climate Change (IPCC) is the United Nations body for assessing the science related to climate change. The IPCC provides regular assessments of the scientific basis of climate change, its impacts and future risks, and options for adaptation and mitigation(...) Created in 1988 by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), the objective of the IPCC is to provide governments at all levels with scientific information that they can use to develop climate policies. IPCC reports are also a key input into international climate change negotiations . Through its assessments, the IPCC identifies the strength of scientific agreement in different areas and indicates where further research is needed. The IPCC does not conduct its own research.(IPCC, s.f.).

CO2 emissions, global temperature change and agreements

It is true that years go by and the world reaches important agreements (accompanied by scientific pillar reports), but we must also recognize that there has been no reduction in CO2 emissions or global temperature change. In short, we are good with words, but bad for actions.

Is the IPCC political?

The IPCC is a scientific body. It reviews and assesses the latest scientific, technical and socio-economic literature produced around the world relevant to the understanding of climate change. It does not conduct any research or monitor climate-related data or parameters. Because of its scientific and intergovernmental nature, the IPCC represents a unique opportunity to provide rigorous and balanced scientific information to decision makers. By endorsing IPCC reports, governments recognize the authority of their scientific content. The organization's work is thus policy-relevant and yet policy-neutral, never prescriptive (IPCC, s.f).

Click on the image to know the magnitude of the risks according to the temperature increase

Key messages

Human-caused climate change is causing dangerous and widespread disruption to nature and is affecting the lives of billions of people around the world, despite efforts to reduce the risks. Over the next two decades, the planet will face several unavoidable climate hazards with global warming of 1.5 °C (2.7 °F). Even if this level of warming is temporarily exceeded, it will generate additional severe impacts, some of which will be irreversible. A total of 127 risks of major concern are identified. Urgent action is needed to address the growing risks.

Science vs politics

This report (which didn't trascend into real action) concluded in 1965 that:

• Through his worldwide industrial civilization, man is unwittingly conducting a vast geophysical experiment. Within a few generations, he is burning the fossil fuels that have slowly accumulated on Earth over the past 500 million years.

• The climatic changes that may result from increased CO2 content could be detrimental to humans.

• By the year 2000, the increase in atmospheric CO2 will approach 25%. This may be sufficient to produce measurable and perhaps marked changes in climate, and will almost certainly cause significant changes in temperature and other properties of the stratosphere.

IPCC structure

The IPCC is an organization of governments that are members of the United Nations or WMO. The IPCC currently has 195 members. Thousands of people from all over the world contribute to the work of the IPCC. For the assessment reports, experts volunteer their time as IPCC authors to assess the thousands of scientific papers published each year to provide a comprehensive summary of what is known about the drivers of climate change, its impacts and future risks, and how adaptation and mitigation can reduce those risks.

On global emissions

Global greenhouse gas emissions have continued to increase, with uneven historical and current contributions from unsustainable energy use, land use and land use change, lifestyles and consumption and production patterns between regions, between and within countries, and between individuals (high confidence).

Click on the image to listen to the explanation of the Climate Action Tracker projection.

Are we to blame?

Surely you have heard about the greenhouse effect in which different gases emitted by human activities retain the heat coming from the sun's rays. Today we know that...

• CO2 levels have changed alarmingly in recent years since the Industrial Revolution

• Most dangerous greenhouse gases are associated with human activities

• CO2 levels have changed alarmingly in the last few years

Net emissions

Put simply, net zero means cutting greenhouse gas emissions to as close to zero as possible, with any remaining emissions re-absorbed from the atmosphere, by oceans and forests for instance. The science shows clearly that in order to avert the worst impacts of climate change and preserve a livable planet, global temperature increase needs to be limited to 1.5°C above pre-industrial levels. Currently, the Earth is already about 1.1°C warmer than it was in the late 1800s, and emissions continue to rise. To keep global warming to no more than 1.5°C – as called for in the Paris Agreement – emissions need to be reduced by 45% by 2030 and reach net zero by 2050. Getting to net zero requires all governments – first and foremost the biggest emitters – to significantly strengthen their Nationally Determined Contributions (NDCs) and take bold, immediate steps towards reducing emissions now.

Transitioning to a net-zero world is one of the greatest challenges humankind has faced. It calls for nothing less than a complete transformation of how we produce, consume, and move about

Now or never (IPCC, 2022)

In the scenarios assessed, limiting warming to around 1.5°C (2.7°F) requires global greenhouse gas emissions to peak before 2025 at the latest, and be reduced by 43% by 2030; at the same time, methane would also need to be reduced by about a third. Even if we do this, it is almost inevitable that we will temporarily exceed this temperature threshold but could return to below it by the end of the century.

Deep, rapid and sustained mitigation and accelerated implementation of adaptation actions in this decade would reduce projected losses and damages for humans and ecosystems (very high confidence), and deliver many co-benefits, especially for air quality and health (high confidence)

IPCC: working groups

The IPCC is divided into three Working Groups and a Task Force. Working Group I deals with The Physical Science Basis of Climate Change, Working Group II with Climate Change Impacts, Adaptation and Vulnerability and Working Group III with Mitigation of Climate Change.

What's the difference?

Effects are the direct consequences of anthropogenic climate change. These include: increased maximum temperatures, increased minimum temperatures, rising sea levels, higher ocean temperatures, increased heavy precipitation (heavy rain and hail), retreating glaciers, thawing permafrost, among others.

Impacts are the indirect consequences of climate change, which directly affect us humans and our environment. These include: an increase in hunger and water crises, especially in developing countries, health risks from rising air temperatures and heat waves, economic consequences of managing secondary damages related to climate change, increasing spread of pests and pathogens, loss of biodiversity due to limited adaptability and speed of adaptation of flora and fauna, ocean acidification due to increased HCO3 concentrations in water because of increased CO₂ concentrations, the need for adaptation in all areas (e.g. agriculture, forestry, energy, infrastructure, tourism, etc.), among others.

The window is clossing

• Adaptation options that are viable and effective today will be limited and less effective with increasing global warming.
• With increasing global warming, losses and damages will increase and other human and natural systems will reach adaptation limits.
• Maladaptation can be avoided through flexible, multi-sectoral, inclusive and long-term planning and implementation of adaptation measures, with co-benefits for many sectors and systems.

We need to act, now

The report provides new estimates of the chances of crossing the 1.5°C global warming level in the coming decades and finds that, unless there are immediate, rapid and large-scale reductions in greenhouse gas emissions, limiting warming to about 1.5°C or even 2°C will be out of reach.

Science vs politics

"The Earth is warmer in 1988 than in the history of instrumental measurements." "There's only a 1 percent chance of an accidental warming of this magnitude.... The greenhouse effect has been detected, and it is changing our climate now" These types of inputs were considered tentative even if the scientific evidence was convincing, it was considered merely tentative.

Climate science has had a long struggle for recognition, as we can see. Even today, we can find that not all governments recognize it. But people change, science develops and so do its institutions.

Natural causes of climate

In discussions among acquaintances or social networks it is common to find arguments such as "it is normal for the climate to change", but is this enough to explain our current situation? No, that is why it is essential to know what systems on our planet cause our climate:

• Earth's orbit
• Volcanic eruptions
• Ocean variability
• Interactions between the components of the climate system

Expected Annual Flood Damage

• Currently, the expected annual damage (DAE) in Mexico from river flooding is US$7 billion and from coastal flooding is US$130 million.
• Tamaulipas, Veracruz and San Luis Potosí will have the highest levels of risk from river flooding; the largest increases in risk are in the center of the country.
• In 2080, due to changes in socioeconomic conditions, the DAE from coastal flooding would increase to $2 billion dollars per year.
• Socioeconomic development plus sea level change leads to DAE of up to $10 billion per year.

Source: Sexta comunicación de México ante la CMNUCC, 2017

Now that you know that climate change and unsustainability crises are an existential threat, it's time to take the next step and ask ourselves, what do I need to know and do to be part of the solutions?

Widespread, rapid and intensified climate change

Climate change is already affecting all regions of the Earth, in multiple ways. The changes we are experiencing will increase with additional warming.

Anthropogenic climate change

Human activities, mainly through greenhouse gas emissions, have unequivocally caused global warming, with the planet's surface temperature reaching 1.1°C above 1850-1900 in 2011-2020.

There should be no doubt that climate change is anthropogenic. This means it is caused by human activity.

Is there a difference?

Climate change refers to long-term changes in the world's weather patterns. On the other hand, global warming describes the gradual increase in the surface temperature of planet Earth. Understanding this distinction will help us to avoid thinking that the only problem we face is an increase in temperature and we can point out bad arguments that are often accompanied by climate change denialism.

"Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period for averaging these variables is 30 years, as defined by the World Meteorological Organization. The relevant quantities are most often surface variables such as temperature, precipitation and wind. Climate in a wider sense is the state, including a statistical description, of the climate system. " (IPCC, 2013:189).

When we talk about climate we have to realize that we are not dealing with something concrete. Climate is not seen out the window. Climate is a set of data, statistics and patterns.