AVERAGE TEMPERATURE

    Panel 1
    Update date
    Authors

    Piero Fraschetti, Francesca Lena, Walter Perconti, Emanuela Piervitali, Giulio Settanta

    Abstract
    Graph
    Abstract

    The indicator describes the trend of mean temperature in Italy.
    The increase in mean temperature recorded in Italy over the last thirty years has often exceeded the global average over land. In 2024, the mean temperature anomaly in Italy, relative to the 1991–2020 climatological baseline, was +1.33 °C—higher than the global land surface anomaly of +1.03 °C. In Italy, 2023 ranked as the warmest year in the entire annual time series starting from 1961. Since 2000, temperature anomalies relative to the 1991–2020 baseline have consistently been positive, except for four years (2004, 2005, 2010, and 2013).

    Description

    Air temperature is one of the key variables that define the climate of a given geographical area.
    The indicator represents the average air temperature, measured at two metres above the ground, over a specific time period. The thermal trend relative to long-term normal values is assessed by calculating anomalies—defined as the difference between the values recorded in a given year and the climatological normal calculated over the reference period 1991–2020.

    Purpose

    It allows for the assessment of ongoing trends in relation to climate change and serves as one of the essential prerequisites for defining appropriate strategies and adaptation actions to address climate change.

    Policy relevance and utility for users
    It is of national scope or applicable to environmental issues at the regional level but of national significance.
    It is able to describe the trend without necessarily providing an evaluation of it.
    It is simple and easy to interpret.
    It provides a representative overview of environmental conditions, environmental pressures, and societal responses.
    It provides a basis for international comparisons
    Analytical soundness
    Be based on international standards and international consensus about its validity;
    Be theoretically well founded in technical and scientific terms
    Presents reliability and validity of measurement and data collection methods
    Temporal comparability
    Spatial comparability
    Measurability (data)
    Adequately documented and of known quality
    Updated at regular intervals in accordance with reliable procedures
    Readily available or made available at a reasonable cost/benefit ratio
    An “adequate” spatial coverage
    An “appropriate” temporal coverage
    Main regulatory references and objectives

    With the European Green Deal, the European Union has placed global warming at the heart of its political agenda, aiming to help limit the increase in global average temperature to 1.5°C above pre-industrial levels and to make territories more resilient to climate change. This commitment is consistent with the goals set by the Paris Agreement under the United Nations Framework Convention on Climate Change (UNFCCC), based on estimates from the Intergovernmental Panel on Climate Change (IPCC). The Paris Agreement is the first universal and legally binding global climate accord, adopted at the Paris Climate Conference (COP21) in December 2015. The EU and its Member States are among the 190 parties to the Paris Agreement. The Agreement sets a long-term goal to "hold the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels, recognizing that this would significantly reduce the risks and impacts of climate change” (UNFCCC, 2016, The Paris Agreement). The need to limit the increase in global average temperature in line with UNFCCC targets is also recognized in the Sendai Framework for Disaster Risk Reduction 2015–2030 and in Goal 13 of the 2030 Agenda for Sustainable Development (“Take urgent action to combat climate change and its impacts”).

    DPSIR
    State
    Impact
    Indicator type
    Descriptive (A)
    References

    https://scia.isprambiente.it;

    Alexandersson H. e Moberg A., 1997, Homogenization of Swedish temperature data, Int. J. of Climatol. , 17, 25-54;

    ISPRA, 2022, I normali climatici 1991-2020 di temperatura e precipitazione in Italia - Stato dell'Ambiente 99/2022

    ISPRA, 2018, Variazioni della temperatura in Italia: estensione della base dati e aggiornamento della metodologia di calcolo - Stato dell’ambiente 81/2018;

    ISPRA, 2016, Controlli di qualità delle serie di temperatura e precipitazione - Stato dell'Ambiente 66/2016

    ISPRA, 2015, Valori climatici normali di temperatura e precipitazione in Italia - Stato dell'Ambiente 55/2015

    ISPRA, 2014, Focus su "Le città e la sfida ai cambiamenti climatici" - Stato dell'Ambiente 54/2014

    ISPRA, 2013, Variazioni e tendenze degli estremi di temperatura e precipitazione in Italia - Stato dell'Ambiente 37/2013

    ISPRA, 2012, Elaborazione delle serie temporali per la stima delle tendenze climatiche - Stato dell'Ambiente 32/2012

    SNPA, 2025, Il clima in Italia nel 2024 - Report ambientali SNPA n. 44/2025

    Toreti A. e Desiato F., 2007, Temperature trend over Italy from 1961 to 2004, Theor. Appl. Climatology, DO I10.1007/s00704-006-0289-6.

    Toreti A., Desiato F., Fioravanti G., Perconti W., 2009, Seasonal temperatures over Italy and their relationship with low-frequency atmospheric circulation patterns, Springer-Climatic Change , DO I: 10.1007/s10584-009-9640-0

    Further actions

    Improvements in the estimation of the average temperature in Italy could derive from the extension of the indicator calculation system to other data sources, in order to increase the availability of historical temperature series that satisfy requirements of duration, continuity and completeness of the time series.

    Data source

    ISPRA

    Data collection frequency
    Yearly
    Data availabilty

    SCIA – Sistema nazionale per l’elaborazione e diffusione di dati climatici (https://scia.isprambiente.it)

    Spatial coverage

    National

    Time coverage

    1961-2024

    Processing methodology

    The programme used by the SCIA system (National System for the Collection, Processing and Dissemination of Climate Data) processes primary data and provides a daily mean temperature value, which is accepted as valid only if it passes specific quality control checks. The programme then calculates the decadal, monthly, and annual values of the indicator by averaging the daily values over 10-day, monthly, and annual periods, respectively. These aggregated values are accepted as valid only if at least 75% of the daily values within each time interval are valid. In accordance with the guidelines of the World Meteorological Organization (WMO), the climatological baseline used for calculating temperature anomalies has been updated to the most recent 30-year period, 1991–2020, in order to better reflect the current climate. By analysing time series using appropriate statistical methods and models, it is possible to detect the presence or absence of temperature trends across Italy, estimate their magnitude, and compare them with trends observed at global or regional scales.

    Update frequency
    Year
    Data quality

    The indicator provides an adequate representation of the trend in mean temperature in Italy. Its calculation is carried out using a standardised methodology, following the general guidelines set by the World Meteorological Organization (WMO). The methodology is consistent over time and space. Both the input data and the indicator itself are subject to validation checks performed by the data owners (CRA-CMA – Research Unit for Climatology and Meteorology applied to Agriculture, Synoptic Network – AM and ENAV, Regional Networks) and by the SCIA system (National System for the Collection, Processing and Dissemination of Climate Data) managed by ISPRA.

    The use of national average anomaly values allows the indicator to effectively meet information needs. The monitoring stations used to calculate anomalies and estimate ongoing trends meet the requirements of duration, continuity, completeness, and homogeneity of time series.

    Status
    Poor
    Trend
    Negative
    State assessment/description

    In 2024 (Figure 1), the mean temperature anomaly in Italy (+1.33 °C) was higher than the global land average anomaly (+1.03 °C), compared to the 1991-2020 climatological baseline.

    Trend assessment/description

    The increase in mean temperature recorded in Italy over the last thirty years has often exceeded the global land average. A significant rise (α = 0.05) in mean temperature in Italy of approximately 0.42 °C per decade was estimated using a simple linear regression model for the period 1981-2024. Since major international climate strategies and policies aim to counteract ongoing warming of the climate system, this unfavorable trend assessment and the assignment of the corresponding indicator can be interpreted as a divergence from that goal.

    Comments

    In Italy, the 2024 mean temperature anomaly ranks 1° highest in the entire historical series. Since 2000, the anomalies relative to the 1991-2020 climatological baseline have been consistently positive, except for four years: 2004, 2005, 2010, and 2013. The year 2024 marked the eleventh consecutive year with a positive anomaly compared to the norm (Figure 1).

    Figure 2 shows that the 2024 annual mean temperature anomaly averaged +1.21 °C in the North, +1.45 °C in the Center, and +1.39 °C in the South and Islands. In 2024, temperature anomalies were positive across all regions and months, with the sole exception of May in Northern Italy, which recorded an anomaly of –0.31 °C. February exhibited record anomalies in all three macro-regions: +3.75 °C in the North, +3.27 °C in the Center, and +2.44 °C in the South and Islands. Subsequently, July and August registered the next highest positive anomalies nationwide.

     

    Data
    File
    File
    Immagine
    Headline

    Figure 1. Time series of annual mean anomalies of near-surface air temperature over land, globally and for Italy, relative to the 1991–2020 climatological normal.

    Data source

    ISPRA

    Immagine
    Headline

    Figure 2. 2024 monthly and annual mean anomalies of near-surface air temperature in Italy, relative to the 1990–2020 climatological normal.

    Data source

    ISPRA

    Graph
    English