Instrumental temperature record

20200324 Global average temperature - NASA-GISS HadCrut NOAA Japan BerkeleyE

Change in Average Temperature With Fahrenheit

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Instrumental temperature record shows the fluctuations of the Earth's temperature as measured by temperature monitoring stations. This record indicates the changes in temperature over various timescales, from decades to centuries, and is a critical component of climate change research. The instrumental temperature record is essential for understanding the global warming trend and for making predictions about the Earth's future climate.

Overview

The instrumental temperature record is based on measurements from land stations and ocean surface ships and buoys. These measurements are collected from thousands of meteorological stations and ocean vessels around the world, providing a comprehensive view of the Earth's temperature changes. The data from these sources are compiled and analyzed by various organizations, including the National Oceanic and Atmospheric Administration (NOAA), the Hadley Centre for Climate Prediction and Research, and the Goddard Institute for Space Studies (GISS).

Data Collection

Temperature data are collected using a variety of instruments, such as thermometers and electronic sensors. These instruments measure the air's temperature at the Earth's surface. Ocean temperature measurements are taken from the surface down to several meters below, using instruments mounted on buoys and ships. The data collected from these instruments undergo quality control processes to ensure their accuracy and reliability.

Historical Records

The instrumental temperature record dates back to the late 19th century, although some records are available from earlier periods. The longest continuous temperature record is the Central England Temperature (CET) series, which starts in 1659. However, global coverage becomes more comprehensive and reliable from the late 19th century onwards, providing a clear picture of temperature trends over the past 150 years.

Temperature Trends

Analysis of the instrumental temperature record shows a clear trend of global warming, particularly since the mid-20th century. The average global surface temperature has increased by approximately 1°C (1.8°F) since the late 19th century. This warming trend is attributed primarily to increased concentrations of greenhouse gases in the atmosphere due to human activities, such as burning fossil fuels and deforestation.

Challenges and Limitations

One of the challenges in interpreting the instrumental temperature record is the variability in data quality and coverage over time and space. Some regions, particularly in the developing world and remote areas, have sparse monitoring networks, leading to uncertainties in regional temperature trends. Additionally, changes in measurement techniques and locations of monitoring stations can introduce biases into the temperature record. Scientists use various methods to adjust for these biases and to fill in gaps in the data.

Importance

The instrumental temperature record is a vital tool for climate scientists. It provides the empirical evidence needed to understand the current state of the climate system, to detect and attribute changes in the Earth's temperature, and to validate climate models. These models are crucial for predicting future climate conditions and for informing policy decisions related to climate change mitigation and adaptation.