25 of 51 US states/DC cut covered-facility emissions while growing real GDP, 2010-2023 — national emissions intensity fell 6.6%

Summary

Using EPA's Greenhouse Gas Reporting Program (GHGRP, large-facility CO2e emissions) against BEA real state GDP (chained 2017 dollars), covered-facility emissions intensity — metric tons of CO2e per million dollars of real state output — fell in 39 of 51 states/DC between 2010 and 2023, and rose in 12. Nationally, aggregate covered-facility intensity fell about 6.6% (GDP grew 34.8% while covered emissions grew 26.0% — output outpaced emissions, so intensity fell even though absolute emissions rose). More strictly, 25 of the 51 states/DC actually cut their absolute covered-facility emissions in tons while growing real GDP over the period — genuine absolute decoupling, not just a slower emissions/output ratio. New Hampshire, Maine, DC, and Maryland showed the steepest intensity declines (roughly -59% to -66%), each combining double-digit real GDP growth with a >50% drop in covered emissions. At the other end, Delaware's intensity nearly tripled (+195%), driven by a large jump in covered facility emissions (+255%) that far outpaced its GDP growth (+20%); Connecticut, Alaska, Hawaii, Mississippi, Minnesota and Texas also saw intensity rise.

Important scope caveat: GHGRP only covers large stationary facilities (power plants, refineries, large manufacturers, etc. — generally >=25,000 metric tons CO2e/year). It excludes transportation, small commercial/residential sources, and most agriculture. This is a proxy for industrial/utility-sector emissions intensity, not each state's total economy-wide greenhouse gas footprint. A state with a lot of untracked transportation or agricultural emissions growth could look better on this measure than its true total-emissions trend.

Method

Query 1 (environment.ghg_facility_annual, an AskAmerica view joining environment.ghg_emissions to environment.ghg_facilities on facility_id+year): summed total_co2e by state_abbr for years 2010 and 2023 — the earliest and latest years GHGRP data is loaded in this corpus (observed coverage 2010–2023).

Query 2 (econ.state_gdp): BEA SAGDP9, line_code='1' ('All industry total', real GDP, millions of chained 2017 dollars) for 2010 and 2023, all 50 states + DC. Real (inflation-adjusted) GDP was used specifically so the ratio isn't distorted by price-level changes over the 13-year window — an important control per this corpus's cost-of-living/inflation recipe guidance.

Joined via geo.state_ref (state_abbr <-> state_fips, since state_gdp's geo_fips carries a 5-digit padded FIPS and ghg_facility_annual carries only state_abbr). Intensity = total_co2e (tons) / real GDP ($M). Percent changes computed in Python (2023 vs 2010) for intensity, GDP, and raw emissions per state; states classified as 'cut and grew' where covered emissions fell AND real GDP rose.

Window choice: 2010 and 2023 were chosen as the endpoints because they are the full observed span of the GHGRP table in this warehouse (2010–2023, confirmed via describe_table) — not an arbitrarily picked interval. This maximizes the trend window available rather than a shorter or cherry-picked span.

Full state ranking

Louisiana and Wyoming carry the highest absolute intensities throughout (over 1,800-2,300 tons/$M) — both have GDP concentrated in emissions-intensive extraction/refining/petrochemicals, so a given dollar of output there requires far more covered-facility emissions than, say, DC or Vermont's service-heavy economies. Absolute intensity level and its trend are different questions; a state can have very high but declining intensity (Kentucky, Indiana, West Virginia) or low but rising intensity (Connecticut, Hawaii).

What explains the outliers

Delaware's emissions nearly quadrupled while GDP grew only modestly — likely reflecting new or expanded large facilities crossing GHGRP's reporting threshold, or a change in fuel mix at existing facilities, rather than broad economic activity; this corpus's environment.ghg_facility_annual view does not carry a reason code, so the driver can't be attributed further from this table alone. Texas, Minnesota, Mississippi, Hawaii, Connecticut and Alaska all saw covered emissions grow far faster than GDP — in Alaska and Louisiana's case aided by essentially flat GDP over the period. Texas is a special case worth flagging: both its GDP (+61.6%) and covered emissions (+129.7%) grew enormously in absolute terms; the state remains a large contributor to both national GDP growth and national covered-emissions growth, so its trend has outsized weight on the 50-state aggregate reported above.

Every query behind this report

6 warehouse calls ran in this session, in order. Each is reproducible against the same snapshot.

SELECT DISTINCT table_name, line_code, description, unit FROM econ.state_gdp WHERE table_name IN ('SAGDP9','SAGDP2','SAGDP1') AND line_code = '1' LIMIT 20

WITH gdp AS (
  SELECT geo_fips, geo_name, "year", data_value AS real_gdp_musd
  FROM econ.state_gdp
  WHERE table_name = 'SAGDP9' AND line_code = '1' AND "year" IN (2010, 2023)
),
em AS (
  SELECT state_abbr, "year", SUM(total_co2e) AS co2e_tons
  FROM environment.ghg_facility_annual
  WHERE "year" IN ('2010','2023') AND state_abbr IS NOT NULL
  GROUP BY state_abbr, "year"
),
joined AS (
  SELECT sr.state_fips, sr.state_abbr, sr.state_name, g."year", g.real_gdp_musd, e.co2e_tons
  FROM em e
  JOIN geo.state_ref sr ON sr.state_abbr = e.state_abbr
  JOIN gdp g ON g.geo_fips = sr.state_fips AND g."year" = CAST(e."year" AS INTEGER)
)
SELECT * FROM joined ORDER BY state_name, "year"

SELECT DISTINCT geo_fips, geo_name FROM econ.state_gdp WHERE table_name='SAGDP9' AND line_code='1' FETCH FIRST 10 ROWS ONLY

SELECT DISTINCT state_fips, state_abbr, state_name FROM geo.state_ref FETCH FIRST 10 ROWS ONLY

SELECT DISTINCT "year" FROM environment.ghg_facility_annual ORDER BY "year"

WITH gdp AS (
  SELECT SUBSTR(geo_fips,1,2) AS state_fips, geo_name, "year", data_value AS real_gdp_musd
  FROM econ.state_gdp
  WHERE table_name = 'SAGDP9' AND line_code = '1' AND "year" IN (2010, 2023)
),
em AS (
  SELECT state_abbr, "year", SUM(total_co2e) AS co2e_tons
  FROM environment.ghg_facility_annual
  WHERE "year" IN ('2010','2023') AND state_abbr IS NOT NULL
  GROUP BY state_abbr, "year"
)
SELECT sr.state_name, sr.state_abbr, g."year", g.real_gdp_musd, e.co2e_tons
FROM em e
JOIN geo.state_ref sr ON sr.state_abbr = e.state_abbr
JOIN gdp g ON g.state_fips = sr.state_fips AND g."year" = CAST(e."year" AS INTEGER)
ORDER BY sr.state_name, g."year"