Latest World News: Have global temperatures ever reached these levels in the last 1

Darrell Kaufman,

As scorching heat spans large swathes of the Earth, many people try to put the extreme temperatures in context and ask themselves: when has it ever been this hot?

Globally, 2023 has seen some of the hottest days in modern measurements, but what about further ahead, before weather stations and satellites?

Some news outlets have reported daily temperatures reaching a 100,000-year high.

Like a paleoclimatic scientist who studies past temperatures, I see where that statement comes from, but I cringe at the inaccurate headlines. While this claim may be correct, there are no detailed temperature records dating back 100,000 years, so we don’t know for sure.

Here’s what we can confidently say about the last time Earth was this hot.

This is a new climatic state

Scientists concluded a few years ago that Earth had entered a new climatic state not seen in over 100,000 years. As a fellow climatologist Nick McKay and I recently discussed in a scientific journal articlethis finding was part of a climate report published by the Intergovernmental Panel on Climate Change (IPCC) in 2021.

Earth was already more than 1 degree Celsius (1.8 Fahrenheit) warmer than in pre-industrial times, and levels of greenhouse gases in the atmosphere were high enough to ensure temperatures would stay high for a long time.

Even in the most optimistic scenarios of the future in which humans stop burning fossil fuels and reduce other greenhouse gas emissions, the average global temperature will most likely remain at least 1°C above pre-industrial temperatures, and possibly much more, for several centuries.

This new climatic state, characterized by a level of global warming of 1 C and more over several centuries, can be reliably compared to temperature reconstructions from a very distant past.

How we estimate past temperature

To reconstruct temperatures before thermometers, paleoclimate scientists rely on information stored in a variety of natural archives.

The most widespread archive dating back thousands of years is found at the bottom of some lakes And oceanswhere an assortment of biological, chemical and physical evidence offers clues to the past. These materials continuously accumulate over time and can be analyzed by extracting a sediment core from the lake bed or ocean floor.

University of Arizona scientist Ellie Broadman holds a sediment core from the bottom of a lake on Alaska’s Kenai Peninsula. Emily Stone

These sediment-based records are rich sources of information that have allowed paleoclimate specialists to reconstruct past global temperatures, but they have important limitations.

For one thing, bottom currents and burrowing organisms can mix the sediments, blurring short-term temperature peaks. On the other hand, the chronology of each record is not precisely known, so when multiple records are averaged together to estimate past global temperature, small-scale fluctuations can be canceled out.

For this reason, paleoclimate specialists are reluctant to compare the long-term record of past temperature with short-term extremes.

Looking back tens of thousands of years

Earth’s average global temperature has fluctuated between glacial and interglacial conditions in cycles lasting about 100,000 years, driven largely by slow, predictable changes. changes in earth’s orbit with concomitant changes in greenhouse gas concentrations in the atmosphere. We are currently in an interglacial period which began about 12,000 years ago with the retreat of the ice caps and the increase in greenhouse gases.

Looking at this 12,000 year interglacial period, the average global temperature over several centuries could have peaked about 6,000 years agobut probably did not exceed the global warming level of 1 C at that time, according to the IPCC report. Another study found that global average temperatures continued to rise throughout the interglacial period. It’s a active research topic.

This means that we have to look further back to find a period that could have been as warm as today.

The last glacial episode lasted nearly 100,000 years. There is no evidence that long-term global temperatures reached pre-industrial baseline at any time during this period.

If we look even further, to the previous interglacial period, which peaked around 125,000 years ago, we find evidence of warmer temperatures. Evidence suggests that the long-term average temperature was probably no more than 1.5 C (2.7 F) above pre-industrial levels not much more than the current level of global warming.

Now what?

Without a rapid and sustained reduction in greenhouse gas emissions, the Earth is currently on course to reach temperatures of about 3 C (5.4 F) above pre-industrial levels by the end of the century, and possibly a bit higher.

At that time, we would need looking back millions years to find a climatic state with such warm temperatures. This would take us back to previous geological epochthe Pliocene, when Earth’s climate was a distant relative of that which supported the rise of agriculture and civilization.

Darrell KaufmanProfessor of Earth and Environmental Sciences,

This article is republished from The conversation under Creative Commons license. Read it original article.

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An Overview of Global Events in 2023

In 2023, the world witnessed a myriad of events that left a lasting impact on global affairs. From political developments and economic shifts to environmental challenges and breakthroughs in science and technology, the year was marked by significant changes and a sense of urgency for collective action. Here’s an overview of some of the latest world news in 2023.

Political Unrest and Diplomatic Strides:
In the political arena, several regions experienced unrest and geopolitical tensions. The ongoing conflict in the Middle East continued to dominate headlines, with efforts towards peace and stability remaining elusive. However, there were also moments of diplomatic breakthroughs as nations engaged in dialogues to ease tensions and work towards lasting solutions.

Economic Transformations:
The global economy faced both challenges and opportunities. Trade disputes between major powers affected markets, while some countries grappled with debt crises. On the other hand, emerging economies showed resilience and promising growth, fueling optimism for a more balanced global economic landscape.

Technological Advancements:
Innovation surged forward in the tech industry, with breakthroughs in artificial intelligence, renewable energy, and space exploration. Quantum computing achieved milestones, promising radical transformations across industries. Renewable energy sources gained traction, with many countries setting ambitious goals to combat climate change.

Climate Crisis and Environmental Resilience:
As the climate crisis intensified, extreme weather events wreaked havoc in various parts of the world. Wildfires, hurricanes, and floods reminded humanity of the urgent need for climate action. In response, governments and communities across the globe doubled down on efforts to reduce carbon emissions, invest in sustainable infrastructure, and protect biodiversity.

Health and Pandemic Management:
Health remained a global priority as countries continued to combat the COVID-19 pandemic. With the emergence of new variants, vaccination efforts and public health measures remained crucial to curbing the spread of the virus. There were also significant advancements in medical research and technology, offering hope for better preparedness in handling future health crises.

Sports and Cultural Milestones:
Amidst the challenges, the world found moments of joy and unity through sports and culture. International sporting events brought together athletes from diverse backgrounds, promoting solidarity and camaraderie. Cultural exchanges and celebrations showcased the richness of human diversity and fostered mutual understanding.

In conclusion, the year 2023 was a dynamic period filled with significant events that shaped the course of history. From political unrest to technological advancements and environmental challenges, the world witnessed the complexities of the global landscape. While obstacles remained, there were also encouraging developments and collaborative efforts towards a more sustainable, peaceful, and prosperous future for all nations. As we move forward, the lessons learned from these events serve as a reminder of the importance of collective action and cooperation to address shared global challenges.