Tropopsphere

Lower Troposphere

August Lower Troposphere
August Anomaly Rank
(45 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
RSS +0.92 +1.66 Coolest 45th 1992 -0.47 -0.85 +0.22 +0.39
Warmest 1st 2023 +0.62 +1.12
June-August Lower Troposphere
June–August Anomaly Rank
(45 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
RSS +0.80 +1.44 Coolest 45th 1985 -0.47 -0.85 +0.21 +0.38
Warmest 1st 2023 +0.62 +1.12
Year-to-Date Lower Troposphere
January–August Anomaly Rank
(45 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
RSS +0.57 +1.03 Coolest 42nd 1985 -0.44 -0.79 +0.20 +0.36
Warmest 3rd 2016 +0.72 +1.30
Ties: 2019

Mid-troposphere

August Mid-troposphere
August Anomaly Rank
(45 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
RSS +0.74 +1.33 Coolest 45th 1985, 1986 -0.32 -0.58 +0.15 +0.28
Warmest 1st 2023 +0.48 +0.86
June-August Mid-troposphere
June–August Anomaly Rank
(45 years*)
Record Years Decadal Trend
°C °F Year °C °F °C °F
RSS +0.62 +1.12 Coolest 45th 1985 -0.40 -0.72 +0.14 +0.26
Warmest 1st 2023 +0.47 +0.85
RATPAC* +0.86 +1.55 Coolest 66th 1965 -0.81 -1.46 +0.19 +0.34
Warmest 1st 2023 +0.72 +1.30

*RATPAC rank is based on 66 years of data

Year-to-Date Mid-troposphere
January–August Anomaly Rank
(45 years*)
Record Years Decadal Trend
°C °F Year °C °F °C °F
RSS +0.35 +0.63 Coolest 40th 1985 -0.33 -0.59 +0.13 +0.23
Warmest 6th 2016 +0.57 +1.03
RATPAC* +0.59 +1.06 Coolest 63rd 1965 -0.89 -1.60 +0.18 +0.32
Warmest 4th 2016 +0.89 +1.60

*RATPAC rank is based on 66 years of data

Stratosphere

Lower Stratosphere

August Lower Stratosphere
August Anomaly Rank
(45 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
RSS -0.32 -0.58 Coolest 14th 2020 -0.60 -1.08 -0.19 -0.35
Warmest 31st 1991 +1.17 +2.11
Ties: 2012
June-August Lower Stratosphere
June–August Anomaly Rank
(45 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
RSS -0.35 -0.63 Coolest 9th 2020 -0.57 -1.03 -0.19 -0.34
Warmest 37th 1982 +0.98 +1.76
Year-to-Date Lower Stratosphere
January–August Anomaly Rank
(45 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
RSS -0.39 -0.70 Coolest 3rd 2016 -0.43 -0.77 -0.19 -0.34
Warmest 43rd 1992 +0.99 +1.78

Background

Temperatures above the Earth's surface are measured within the lower troposphere, middle troposphere, and stratosphere using in-situ balloon-borne instruments (radiosondes) and polar-orbiting satellites (NOAA's TIROS-N). The radiosonde and satellite records have been adjusted to remove time-dependent biases (artificialities caused by changes in radiosonde instruments and measurement practices as well as changes in satellite instruments and orbital features through time). Global averages from radiosonde data are available from 1958 to present, while satellite measurements date back to 1979.

The mid-troposphere temperatures are centered in the in the atmospheric layer approximately 3–10 km [2–6 miles] above the Earth's surface, which also includes a portion of the lower stratosphere. (The Microwave Sounding Unit [MSU] channel used to measure mid-tropospheric temperatures receives about 25 percent of its signal above 10 km [6 miles].) Because the stratosphere has cooled due to increasing greenhouse gases in the troposphere and losses of ozone in the stratosphere, the stratospheric contribution to the tropospheric average, as measured from satellites, creates an artificial component of cooling to the mid-troposphere temperatures. The University of Washington (UW) versions of the UAH and RSS analyses attempt to remove the stratospheric influence from the mid-troposphere measurements, and as a result the UW versions tend to have a larger warming trend than either the UAH or RSS versions. For additional information, please see NCEI's Microwave Sounding Unit page.

The radiosonde data used in this global analysis were developed using the Lanzante, Klein, Seidel (2003) ("LKS") bias-adjusted dataset and the First Difference Method (Free et al. 2004) (RATPAC). Additional details are available. Satellite data have been adjusted by the Global Hydrology and Climate Center at the University of Alabama in Huntsville (UAH). An independent analysis is also performed by Remote Sensing Systems (RSS) and a third analysis has been performed by Dr. Qiang Fu of the University of Washington (UW) (Fu et al. 2004)** to remove the influence of the stratosphere on the mid-troposphere value. Global averages from radiosonde data are available from 1958 to present, while satellite measurements began in 1979.

References


Citing This Report

NOAA National Centers for Environmental Information, Monthly Upper Air Report for August 2023, published online September 2023, retrieved on July 14, 2024 from https://www.ncei.noaa.gov/access/monitoring/monthly-report/upper-air/202308.