Atmospheric

The CogFx study at Harvard found that cognitive scores for strategy, information usage and crisis response dropped by an average of 50% when indoor CO₂ rose from 550 ppm to 1,400 ppm.

This is because CO₂ concentrations above 1,000 ppm reduce cerebral blood flow and impair executive function. A poorly ventilated office or classroom routinely exceeds this threshold within 45 minutes of full occupancy.

This leads to millions of people making important decisions, studying for exams and managing complex tasks while functionally impaired by the air they breathe, without ever knowing it.

Allen et al. (2016, Environmental Health Perspectives) placed twenty-four knowledge workers in a controlled office environment and varied CO2 concentrations across three levels: 550 ppm (green building), 945 ppm (conventional building) and 1,400 ppm (conventional building with added CO2). Cognitive function was assessed using the Strategic Management Simulation. At 945 ppm, scores on complex strategic thinking tasks declined by fifteen per cent compared to 550 ppm. At 1,400 ppm, the decline exceeded fifty per cent for crisis response and strategy tasks.

This is because elevated CO2 increases cerebral blood flow (via vasodilation) and reduces blood pH (respiratory acidosis), both of which affect neurotransmitter kinetics and synaptic efficiency. The prefrontal cortex, responsible for executive function and complex decision-making, is disproportionately sensitive to metabolic perturbations. Satish et al. (2012, Environmental Health Perspectives) found similar cognitive impairments at 1,000 ppm in an independent study, confirming the dose-response relationship.

Outdoor CO2 is currently approximately 424 ppm (NOAA, 2024). Occupied meeting rooms routinely reach 1,500 to 3,000 ppm within thirty minutes (Persily and de Jonge, 2017, Indoor Air). Bedrooms with closed doors reach 1,000 to 2,500 ppm overnight. Classrooms with thirty students commonly exceed 2,000 ppm. The cognitive impairment threshold documented by Allen et al. is exceeded in the majority of indoor spaces where knowledge work, learning and decision-making occur. Opening a window is the simplest intervention; it is also the one most compromised by modern sealed building design.

Myopia prevalence has doubled in the past 30 years. Systematic reviews confirm outdoor time is protective, with each additional hour per week reducing risk by approximately two percent.

The mechanism is dopamine release in the retina triggered by bright outdoor light intensities (10,000+ lux) that indoor environments never reach. Children who spend more time outdoors develop myopia at lower rates regardless of near-work levels.

Ordinary room light (100-200 lux) suppresses melatonin production by up to 50%. Brighter indoor environments and screen use after sunset suppress it further.

This is because melanopsin-containing retinal ganglion cells signal the suprachiasmatic nucleus to delay melatonin onset. The signal is strongest in the 460-480nm blue wavelength range.

Lee et al. published in Atmospheric Environment in 2021 that contrail cirrus effective radiative forcing was 57.4 milliwatts per square metre for 2018.

Aviation CO2 forcing was 34 milliwatts per square metre.

Contrails are the single largest aviation climate forcing component, larger than the carbon emissions themselves.

Aviation contributed 3.5% of total anthropogenic effective radiative forcing.

Teoh et al. published in Atmospheric Chemistry and Physics in 2024 that regional contrail net radiative forcing was highest over Europe at 876 milliwatts per square metre and the USA at 414.

Just 2% of flights cause 80% of annual contrail energy forcing.

During COVID-19 lockdowns, a 43% reduction in flight distance produced a 56% reduction in contrail radiative forcing.

The relationship between what is in the sky and what reaches the ground is measurable, significant and not widely discussed.

Global population-weighted exposure to wildfire-generated PM2.5 increased by 52% between 2000 and 2019, driven by rising fire frequency in Australia, western North America and Siberia.

This is because climate patterns have extended fire seasons and dried out vegetation, while decades of fire suppression created accumulated fuel loads. When these forests burn, the particulate matter is chemically distinct from urban pollution: it carries oxidised organic compounds that penetrate deep into lung tissue.

This leads to measurable increases in emergency department admissions for asthma, COPD exacerbations and cardiovascular events, with effects persisting for weeks after smoke clears. Children and the elderly absorb disproportionate doses.

The UK sits between 50 and 59 degrees north latitude.

From approximately October through March, UVB radiation at these latitudes is insufficient for cutaneous vitamin D synthesis.

This is the vitamin D winter.

SACN's 2016 report set a reference nutrient intake of 10 micrograms per day for everyone aged 4 and above, acknowledging it could not quantify sun derived vitamin D.

National Diet and Nutrition Survey data shows 23% of adults aged 19 to 64 have low vitamin D levels.

Serum concentrations fall approximately fifty percent from September peak to February trough.

PHE monitoring from 1989 to 2008 found erythemal UV radiation increased at a rate of 1.68% per year, likely from reduced aerosol pollution.

However this increase is not large enough to significantly alter the fundamental vitamin D winter.

The dominant drivers remain latitude, seasonal UV patterns, time spent indoors, clothing and skin pigmentation.

Loladze (2014, eLife) compiled data from 130 plant varieties and found that rising atmospheric CO2 concentrations are reducing the mineral content of crops. Across all species studied, zinc declined by 9.3%, iron by 8.1% and protein by 6.3% at elevated CO2 levels. Myers et al. (2014, Nature) analysed crops grown at FACE (Free-Air CO2 Enrichment) sites simulating 2050 CO2 levels and confirmed significant declines in zinc (3-11%), iron (4-10%) and protein (6-8%) in wheat, rice, peas and soybeans.

This is because elevated CO2 accelerates photosynthesis, causing plants to grow faster and accumulate more carbohydrate (diluting minerals). The "junk food effect" means plants produce more biomass with less nutritional density. Zhu et al. (2018, Science Advances) estimated that by 2050, elevated CO2 will place an additional 175 million people into zinc deficiency and 122 million into protein deficiency globally.

The compound effect is alarming: crops are simultaneously losing nutrients from depleted soils (Davis et al., 2004), losing nutrients from selective breeding for yield over nutrition (Thomas, 2003) and now losing nutrients from the atmosphere itself. A carrot grown in 1950, in mineral-rich soil, at 310 ppm CO2, contained meaningfully more nutrition per gram than an identical variety grown today at 420 ppm CO2 in depleted soil. The food looks the same but delivers less.

Stanhill and Cohen published the foundational study in Agricultural and Forest Meteorology in 2001, documenting a global average reduction of 0.51 watts per square metre per year.

That equates to 2.7% per decade from the 1950s to the 1990s.

Wild et al. published the reversal in Science in 2005: widespread brightening since the late 1980s across the Northern Hemisphere.

The cause is well established: anthropogenic aerosol pollution, primarily sulphates from fossil fuel combustion, reduced atmospheric transparency.

Subsequent emission reductions from Clean Air Acts, EU legislation and the collapse of Eastern Bloc industry allowed solar radiation to recover.

Wild et al. argued in 2007 that dimming partially masked greenhouse warming until the 1980s, with brightening uncovering the full greenhouse effect.

The phenomenon is not disputed. It is measured by instruments across thousands of sites worldwide.

The question is what else has been put into the atmosphere, by whom and whether all of it has been accounted for.

Met Office pyranometer stations have collected hourly solar radiation data spanning 1947 to 2023.

The dataset is publicly available as the MIDAS Open dataset.

A 2023 study in Theoretical and Applied Climatology using Met Office sunshine series confirmed a continuing brightening trend since the mid 1980s.

No surface level circulation trend was sufficient to explain the change, implicating reduced aerosol loads as the primary driver.

European monitoring sites showed up to 60% decline in aerosol optical depth since the 1980s.

DEFRA's Heavy Metals Network routinely measures arsenic, cadmium, chromium, cobalt, copper, iron, manganese, nickel, lead, selenium, vanadium and zinc in PM10 across 24 sites.

Aluminium, barium and strontium are not monitored in this compliance network.

There are no UK or EU regulatory limit values or target values for aluminium, barium, or strontium in ambient air.

NDNS data show 39% of UK girls aged 11-18 have vitamin D levels below 25 nmol/L during winter months. This is the threshold the government defines as deficient.

Vitamin D functions as a hormone regulating over 200 genes. Deficiency during development affects bone mineralisation, immune function and hormonal maturation.

Firstenberg (2017, The Invisible Rainbow) documented that ambient electromagnetic radiation in the 1 MHz to 300 GHz range has increased by a factor of approximately 10^18 (one quintillion) since 1900. Before electrification, the only sources of electromagnetic fields at these frequencies were atmospheric events (lightning) and cosmic background radiation. Today, the electromagnetic environment includes mobile phone towers, Wi-Fi routers, Bluetooth devices, smart meters, power lines, radar, satellite communications and 5G millimetre-wave transmitters, creating a continuous bath of non-native electromagnetic fields.

This is because every subsequent generation of wireless technology operates at higher frequencies and greater power densities. Pall (2018, Journal of Chemical Neuroanatomy) identified the mechanism by which these fields affect biology: voltage-gated calcium channels (VGCCs) in cell membranes are activated by electromagnetic fields at intensities far below thermal thresholds. VGCC activation triggers excessive intracellular calcium influx, which in turn activates nitric oxide synthase, generating peroxynitrite (a potent oxidative stressor). This mechanism explains non-thermal biological effects that the current regulatory framework (based solely on thermal effects) does not address.

The International Commission on Non-Ionizing Radiation Protection (ICNIRP) safety limits are based exclusively on preventing tissue heating within a 6-minute exposure window. They do not account for chronic, low-level, non-thermal exposure over years, nor for cumulative exposure from multiple simultaneous sources, nor for vulnerable populations (developing foetuses, children). The BioInitiative Report (2012), compiled by 29 independent scientists, reviewed over 1,800 studies and concluded that existing safety standards are inadequate by a factor of 1,000 to 10,000 for protection against non-thermal biological effects.