<p>When I was born in 1951, earth's atmospheric CO<sub>2</sub> concentration was around 310 mg kg<sup>−1</sup> (i.e., parts per million), with an annual rate of increase averaging some 0.8 mg kg<sup>−1</sup> per year (NOAA, <span>2024</span>). When I commenced my research career in 1984, atmospheric CO<sub>2</sub> concentration was 340 mg kg<sup>−1</sup>, with a decadal average increase for the 1980s of 1.6 mg kg<sup>−1</sup> per year. In August 2024, atmospheric CO<sub>2</sub> concentration was reported as 423 mg kg<sup>−1</sup>, with the decadal mean annual increase for the 2010s nearing 2.5 mg kg<sup>−1</sup> per year (NOAA, <span>2024</span>). In the same period, Earth's human population has increased from 2.5 to 8.0 billion. Science says the increase in atmospheric CO<sub>2</sub>, together with other trace gases, notably methane and nitrous oxide, will decrease the proportion of insolation received by earth that is reflected back into space, and so warm the planet. The expectation of global temperature increase is the climate change story; it has been told repeatedly in many forums such as the IPCC documents and debated at great length by “believers” and “deniers.” I will not dwell on it here.</p><p>There is ample evidence that the predictions are being fulfilled (see, e.g., Figure 2 of Yuan & Hou, <span>2015</span>). The acceptance of climate change as fact is now mainstream, with the global temperature rise to date frequently stated to be in the vicinity of 1.1°C (IPCC, <span>2023</span>). Europe is leading the way among nations in transforming lifestyles to achieve carbon neutrality (EU, <span>2020</span>). The increase in atmospheric CO<sub>2</sub> and population increase are closely linked. Fundamentally, humans need energy to drive their homes, motorcars, and industries; much of this energy comes from burning fossil fuels, thereby releasing CO<sub>2</sub> into the atmosphere that was sequestered in past geological eras. What intuitively perturbs me about the raw NOAA data is that the rate of increase in atmospheric CO<sub>2</sub> concentration is still increasing. After all the international effort, I had thought that the annual rate of global atmospheric CO<sub>2</sub> increase would be falling by now, not still rising.</p><p>I turn to the 2023 IPCC 6th Assessment report for guidance as to the status of the collective international effort in climate change mitigation. For me, the report does not join the dots and only increases my feeling of concern. “Summary for policymakers, Figure 5” is telling; it depicts annual global emissions of CO<sub>2</sub> equivalents around 55 Gt per year, and shows that this needs to be halved by 2040 to limit warming to 1.5–2°C. I wondered to myself what the current annual CO<sub>2</sub> increase of 3 mg kg<sup>−1</sup> per year would convert into in units of Gt, so I looked up the weight of the earth's atmosphere—5.15 million Gt. Thus, a 3 mg kg<sup>−1</sup> annual increase is about 15.5 Gt. Allowin
{"title":"Our world is changing","authors":"Cory Matthew","doi":"10.1002/glr2.12102","DOIUrl":"https://doi.org/10.1002/glr2.12102","url":null,"abstract":"<p>When I was born in 1951, earth's atmospheric CO<sub>2</sub> concentration was around 310 mg kg<sup>−1</sup> (i.e., parts per million), with an annual rate of increase averaging some 0.8 mg kg<sup>−1</sup> per year (NOAA, <span>2024</span>). When I commenced my research career in 1984, atmospheric CO<sub>2</sub> concentration was 340 mg kg<sup>−1</sup>, with a decadal average increase for the 1980s of 1.6 mg kg<sup>−1</sup> per year. In August 2024, atmospheric CO<sub>2</sub> concentration was reported as 423 mg kg<sup>−1</sup>, with the decadal mean annual increase for the 2010s nearing 2.5 mg kg<sup>−1</sup> per year (NOAA, <span>2024</span>). In the same period, Earth's human population has increased from 2.5 to 8.0 billion. Science says the increase in atmospheric CO<sub>2</sub>, together with other trace gases, notably methane and nitrous oxide, will decrease the proportion of insolation received by earth that is reflected back into space, and so warm the planet. The expectation of global temperature increase is the climate change story; it has been told repeatedly in many forums such as the IPCC documents and debated at great length by “believers” and “deniers.” I will not dwell on it here.</p><p>There is ample evidence that the predictions are being fulfilled (see, e.g., Figure 2 of Yuan & Hou, <span>2015</span>). The acceptance of climate change as fact is now mainstream, with the global temperature rise to date frequently stated to be in the vicinity of 1.1°C (IPCC, <span>2023</span>). Europe is leading the way among nations in transforming lifestyles to achieve carbon neutrality (EU, <span>2020</span>). The increase in atmospheric CO<sub>2</sub> and population increase are closely linked. Fundamentally, humans need energy to drive their homes, motorcars, and industries; much of this energy comes from burning fossil fuels, thereby releasing CO<sub>2</sub> into the atmosphere that was sequestered in past geological eras. What intuitively perturbs me about the raw NOAA data is that the rate of increase in atmospheric CO<sub>2</sub> concentration is still increasing. After all the international effort, I had thought that the annual rate of global atmospheric CO<sub>2</sub> increase would be falling by now, not still rising.</p><p>I turn to the 2023 IPCC 6th Assessment report for guidance as to the status of the collective international effort in climate change mitigation. For me, the report does not join the dots and only increases my feeling of concern. “Summary for policymakers, Figure 5” is telling; it depicts annual global emissions of CO<sub>2</sub> equivalents around 55 Gt per year, and shows that this needs to be halved by 2040 to limit warming to 1.5–2°C. I wondered to myself what the current annual CO<sub>2</sub> increase of 3 mg kg<sup>−1</sup> per year would convert into in units of Gt, so I looked up the weight of the earth's atmosphere—5.15 million Gt. Thus, a 3 mg kg<sup>−1</sup> annual increase is about 15.5 Gt. Allowin","PeriodicalId":100593,"journal":{"name":"Grassland Research","volume":"3 3","pages":"217-218"},"PeriodicalIF":0.0,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/glr2.12102","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Luis A. Vallejos-Fernández, Ricardo Guillén, César Pinares-Patiño, Rubén García-Ticllacuri, Yudith Y. Muñoz-Vilchez, Carlos Quilcate, Wuesley Y. Alvarez-García