Met6: The scientific consensus on why Earth's temperature is increasing (v1.1)

  We now understand the mechanics of Earth's atmospheric layers, how the planet balances its radiation budget, and how convection and conduction move that heat around. With those scientific foundations established, we can state the definitive verdict on why Earth’s temperature has been rapidly increasing—at least since 1970.

The verdict is backed by an overwhelming, virtually unanimous scientific consensus: Global climate change is happening, it is driven by human activity, and the primary mechanism is the emission of greenhouse gases.

The Scale of Agreeing Science

The global scientific consensus does not exist in a vacuum; it is the collective echo of tens of thousands of individual peer-reviewed papers published in refereed scientific journals.

The Institute for Scientific Information (ISI) maintains a comprehensive database of these academic publications. Since 2012 alone, over 88,125 English-language climate science papers have been published. Multiple independent sampling studies of this database show that the consensus among active climate scientists has breached 97%, with a comprehensive 2021 study concluding that the agreement on the human cause of modern climate change stands at greater than 99%.

In the international scientific community, the human role in modern climate change is formally considered both "unequivocal" and "incontrovertible."

Statements from Leading Scientific Associations

To see the depth of this agreement, we can look directly at the official position statements issued by the peak scientific, medical, and geographic institutions of the world:

  • Joint Statement of 11 International Science Academies (2005): "Climate change is real. There will always be uncertainty in understanding a system as complex as the world’s climate. However, there is now strong evidence that significant global warming is occurring... It is likely that most of the warming in recent decades can be attributed to human activities."

  • Statement on Climate Change from 18 Scientific Associations (2009): "Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver."

  • American Association for the Advancement of Science (AAAS): "Based on well-established evidence, about 97% of climate scientists have concluded that human-caused climate change is happening."

  • American Chemical Society (ACS): "The Earth’s climate is changing in response to increasing concentrations of greenhouse gases (GHGs) and particulate matter in the atmosphere, largely as the result of human activities."

  • American Geophysical Union (AGU): "Based on extensive scientific evidence, it is extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century. There is no alternative explanation supported by convincing evidence."

  • American Medical Association (AMA): "Our AMA... supports the findings of the Intergovernmental Panel on Climate Change’s assessment reports and concurs with the scientific consensus that the Earth is undergoing adverse global climate change and that anthropogenic contributions are significant."

  • American Meteorological Society (AMS): "Research has found a human influence on the climate of the past several decades... It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-twentieth century."

  • American Physical Society (APS): "While natural sources of climate variability are significant, multiple lines of evidence indicate that human influences have had an increasingly dominant effect on global climate warming observed since the mid-twentieth century."

  • The Geological Society of America (GSA): "The Geological Society of America concurs with assessments... that global climate has warmed in response to increasing concentrations of carbon dioxide ($\text{CO}_2$) and other greenhouse gases... Human activities are the dominant cause of the rapid warming since the middle 1900s."

  • U.S. National Academy of Sciences: "Scientists have known for some time, from multiple lines of evidence, that humans are changing Earth’s climate, primarily through greenhouse gas emissions."

  • U.S. Global Change Research Program (USGCRP): "Earth’s climate is now changing faster than at any point in the history of modern civilization, primarily as a result of human activities."

  • Intergovernmental Panel on Climate Change (IPCC): "It is unequivocal that the increase of $\text{CO}_2$, methane, and nitrous oxide in the atmosphere over the industrial era is the result of human activities and that human influence is the principal driver... Since systematic scientific assessments began in the 1970s, the influence of human activity on the warming of the climate system has evolved from theory to established fact."

🌐 Note: A complete index of nearly 200 worldwide scientific organizations holding this explicit position can be reviewed via the California Office of Planning and Research Tracking Index.

Global Emissions Tracking

When we look at the raw physical data driving these consensus statements, the global atmospheric tracking charts show an unmistakable upward trajectory in total greenhouse gas volumes.

When broken down by economic sector, the global sources of these emissions map out as follows:

Because countries vary drastically in population and industrialization, comparing absolute emissions can be misleading. To view the data objectively, scientists analyze per capita greenhouse gas emissions across various nations. This metric tracks the average tonnage of gas generated per person each year, highlighting the stark variations in carbon footprints between industrial, developing, and resource-reliant economies.

Localizing the Data: The Hawaii Footprint

To see how these planetary numbers manifest locally, we can examine the specific emissions ledger for the state of Hawaii. In 2020, Hawaii's total gross emissions reached 16.32 Million Metric Tons (MMT) of $\text{CO}_2$ equivalent. When factoring in natural carbon sinks—such as land use, forestry, and active plant photosynthesis—the net statewide total was 13.64 MMT.

The local breakdown by economic sector reveals a unique profile dominated heavily by island energy requirements:

HAWAII EMISSIONS BY SECTOR (2020)
┌───────────────────────────────────────────────────────────┐ 85.8% Energy
│■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■ │ (Fossil Fuels for Power/Transport)
└───────────────────────────────────────────────────────────┘
│■■■■│ 6.1% AFOLU (Agriculture, Forestry, Land Use)
│■■│   4.1% IPPU (Industrial Processes & Product Use)
│■■│   4.0% Waste Management

When we parse these local emissions by the specific molecular species involved, the greenhouse blanket is overwhelmingly carbon-heavy:

  • Carbon Dioxide ($\text{CO}_2$): $88.9\%$ (driven almost exclusively by the burning of imported petroleum for electricity and transport)

  • Methane ($\text{CH}_4$): $5.4\%$

  • Synthetic Halocarbons (HFCs/PFCs): $4.0\%$ (industrial cooling agents)

  • Nitrous Oxide ($\text{N}_2\text{O}$): $1.7\%$

The data is clear, whether viewed from a global satellite grid or measured directly from an island in the Pacific. The warming of our atmosphere is no longer a theoretical projection; it is a thoroughly documented, empirical fact.

Some useful charts but could be somewhat dated but trends remain consistent with current findings. 





Comments

Post a Comment