All Variables

Below is a library of all variables available within ClimateData.ca. Use the filter to limit your search to specific types of data.

This is the highest maximum temperature value in this time period. For more information about the source data and figures, click here.

 

Mean temperature is the average temperature on a given day and is usually obtained by averaging the daily maximum and minimum temperatures. For more information about the source data and figures, click here.

This is the average minimum temperature for a given time period and is derived by averaging all the daily minimum temperatures in that time period. For more information about the source data and figures, click here.

This is the average maximum temperature for a given time period and is derived by averaging all the daily maximum temperatures in that time period. For more information about the source data and figures, click here.

The number of days with minimum temperatures less than ‑15°C gives an indication of the number of very cold days in a given time period. For more information about the source data and figures, click here.

The number of days with minimum temperatures less than ‑25°C gives an indication of the number of extreme cold days in a given time period. For more information about the source data and figures, click here.

This is the number of days when daily maximum temperature is greater than 25°C and gives an indication of the number of summer days. For more information about the source data and figures, click here.

This is the number of days when daily maximum temperature is greater than 27°C. For more information about the source data and figures, click here.

This is the number of days when daily maximum temperature is greater than 29°C. For more information about the source data and figures, click here.

This is the number of days when daily maximum temperature is greater than 30°C and gives an indication of the number of very hot days. For more information about the source data and figures, click here.

This is the number of days when daily maximum temperature is greater than 32°C. For more information about the source data and figures, click here.

This is the lowest minimum temperature value in this time period. For more information about the source data and figures, click here.

The last spring frost marks the approximate beginning of the growing season for frost-sensitive crops and plants. The date of the last spring frost is the first occurrence of at least one consecutive day with minimum temperature greater than 0°C (Tmin > 0) before July 15.

The first fall frost marks the approximate end of the growing season for frost-sensitive crops and plants. The date of the first fall frost is the first occurrence of at least one consecutive day with minimum temperature less than 0°C (Tmin < 0) after July 15.

The Frost-Free Season is the approximate length of the growing season, during which there are no freezing temperatures to kill or damage plants. This is the number of days between the Last Spring Frost and the First Fall Frost.

This is the largest precipitation total on a single day. For more information about the source data and figures, click here.

Number of days with daily precipitation totals greater than 1 mm. For more information about the source data and figures, click here.

Number of days with daily precipitation totals greater than 10 mm. For more information about the source data and figures, click here.

Number of days with daily precipitation totals greater than 20 mm. For more information about the source data and figures, click here.

The maximum number of consecutive days with precipitation below 1mm/day, within the selected time period.

The number of periods with 5 or more consecutive days with precipitation below 1mm/day, within the selected time period.

This is the total precipitation (rain and snow) for a given time period. For more information about the source data and figures, click here.

The maximum total precipitation that falls over a consecutive 5-day period.

The Standardised Precipitation Evapotranspiration Index (SPEI) is a drought index based on the difference between precipitation (P) and potential evapotranspiration (PET). The inclusion of PET means that the SPEI can account for the effects of increased temperatures on water demand. Negative (positive) values indicate water deficit (surplus).

SPEI-3 corresponds to the SPEI of one month and the previous 2 months. For example, to look at SPEI values for summer (June, July and August), select August in the drop-down menu. The SPEI values displayed are for August and the previous 2 months, so June to August

The Standardised Precipitation Evapotranspiration Index (SPEI) is a drought index based on the difference between precipitation (P) and potential evapotranspiration (PET). The inclusion of PET means that the SPEI can account for the effects of increased temperatures on water demand. Negative (positive) values indicate water deficit (surplus).

SPEI-12 corresponds to the SPEI of one month and the previous 11 months. For example, to look at SPEI values for the year, select December in the drop-down menu. The SPEI values displayed are for December and the previous 11 months, so January to December.

This is the number days when daily minimum temperature is less than 0°C and indicates when conditions are below freezing, usually overnight. For more information about the source data and figures, click here.

Cooling degree days give an indication of the amount of air conditioning that may be required to maintain comfortable conditions in a building during warmer months. A threshold temperature of 18°C is used and for any day when the mean temperature exceeds this value, cooling degree days are accrued. So, if the daily mean temperature on a given day is 24°C, then 6 CDDs are accrued for this day. CDD values are totalled over the year; the larger the CDD value the greater the requirement for air conditioning.

For more information about the source data and figures, click here.

Projections of Relative Sea-Level Change (developed by Natural Resources Canada)

To help Canadians plan, prepare for, and remain resilient to projected sea-level changes, Natural Resources Canada (NRCan) has developed a new dataset of present and future relative sea-levels (James et al., 2021). The dataset provides projections for relative sea-level change, which is the change in ocean height relative to land and is the apparent sea-level change experienced by coastal communities and ecosystems.  It is a combined measure of both changes to ocean levels due to climate change and vertical land movements, as described below.

Projections are available at a resolution of 0.1° (approximately 11 km latitude, 2-8 km longitude), and for 2006 and every decade from 2010-2100, relative to 1986-2005 conditions. The data is available for the three Representative Concentration Pathways (RCP) emissions scenarios (RCP 2.6, RCP 4.5, RCP 8.5) and an enhanced scenario.

Use relative sea-level rise data together with other types of data

When  combined with other types of data such as estimates of storm surge, waves, tides, and additional local-scale vertical land motion, such as subsidence on river deltas, this relative sea-level data is expected to contribute significantly to coastal flood risk assessments and adaptation decision-making.

Relative sea-level change varies greatly based on where you live in Canada

Relative sea-level change along Canada’s coastlines varies greatly from location to location, and can differ substantially from the projected global average sea-level change.  Some Canadian coastlines in Atlantic Canada can expect relative sea-level rise that is larger than the projected global sea-level rise. Conversely, other Canadian coastlines, where the land is rising faster than the ocean, such as Hudson Bay and much of the Canadian Arctic Archipelago, can expect a relative sea-level fall.

Guidance on emissions scenarios

Data estimates are available for three RCP scenarios: RCP 2.6 (low), RCP 4.5 (medium), and RCP 8.5 (high) – as reported in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR5; Church et al, 2013a,b).  For each scenario, lower, median and upper estimates of projected relative sea-level change are provided, corresponding to the 5th, 50th and 95th percentiles of the full ensemble of Global Climate Models.  An additional Enhanced Scenario is also available, described below.  All projections are based on open ocean basin changes that are extrapolated to the coastline (which does not include explicit modelling of shallow water effects).

For long-term decisions that may be influenced by sea-level changes, the precautionary principle would indicate using the 95th percentile values of the high-emission (RCP 8.5) scenario.  In the case of low tolerance to risk and for project time frames extending past 2100, it would be prudent to consider the enhanced scenario described below. The enhanced scenario adds a further 65 cm of global sea-level rise to the median projection of the highest (RCP8.5) climate scenario at 2100. This 65 cm reflects a potential additional contribution from the Antarctic Ice Sheet. In other situations, use of higher or lower sea-level values, or a range of projected sea-level change, may be more appropriate.  For detailed technical guidance on the use of sea-level projections see Relative sea-level projections for Canada based on the IPCC Fifth Assessment Report and the NAD83v70VG national crustal velocity model (James et al, 2021) and GEOSCAN for the full publication and data.

More about this dataset

Projected sea-level changes in this dataset include the effects of changes in glacier and ice-sheet mass loss, thermal expansion of the oceans, changing ocean circulation conditions, and human-caused changes in land water storage, as summarized in IPCC AR5.  A new land motion model developed by the Canadian Geodetic Survey (Robin et al., 2020; Canadian Geodetic Survey, 2019) was incorporated into the data to replace less-accurate land motion values utilized by the IPCC AR5.

Vertical land movements in Canada largely result from loading and unloading of the Earth’s surface by ice sheets.  During the last ice age that ended about seven thousand years ago, much of Canada was covered with thick ice sheets that weighed down the surface of the Earth.  Deep within the Earth, rock yielded and flowed and the land under the ice was pushed down.  At the edges of the ice sheets, the land was pushed up.  Following the thinning and retreat of those ice sheets, land that was pushed down started to rise, while land that was uplifted began to sink, a process that continues to the present day.  Tectonic effects causing earthquakes and land subsidence caused by sediment compaction on coastal deltas can also generate vertical movements that contribute to relative sea-level change, but these are not accounted for in these projections.

References

  • Canadian Geodetic Survey. (2019). NAD83(CSRS) v7. https://webapp.geod.nrcan.gc.ca/geod/tools-outils/nad83-docs.php
  • Church, J.A., P.U. Clark, A. Cazenave, J.M. Gregory, S. Jevrejeva, A. Levermann, M.A. Merrifield, G.A. Milne, R.S. Nerem, P.D. Nunn, A.J. Payne, W.T. Pfeffer, D. Stammer and A.S. Unnikrishnan, 2013a. Sea Level Change. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
  • Church, J.A., P.U. Clark, A. Cazenave, J.M. Gregory, S. Jevrejeva, A. Levermann, M.A. Merrifield, G.A. Milne, R.S. Nerem, P.D. Nunn, A.J. Payne, W.T. Pfeffer, D. Stammer and A.S. Unnikrishnan, 2013b. Sea Level Change Supplementary Material. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]
  • James, T.S., Robin, C., Henton, J.A., and Craymer, M., 2021. Relative Sea-level Projections for Canada based on the IPCC Fifth Asssessment Report and the NAD83v70VG National Crustal Velocity Model; Geological Survey of Canada, Open  File 8764, 1 .zip file, https://doi.org/10.4095/327878
  • Robin, C.M.I., Craymer, M., Ferland, R., James, T.S., Lapelle, E., Piraszewski, M., and Zhao, Y., 2020. NAD83v70VG:  A new national crustal velocity model for Canada; Geomatics Canada, Open File 0062, 1 .zip file,  https://doi.org/10.4095/327592

Growing degree days are a measure of whether climate conditions are warm enough to support plant growth. When the daily mean temperature exceeds the threshold temperature, growing degree days are accrued. A threshold temperature of 10°C is generally used for crops such as corn and beans that require warmer temperatures to reach maturity. For more information about the source data and figures, click here.

Growing degree days are a measure of whether climate conditions are warm enough to support plant growth. When the daily mean temperature exceeds the threshold temperature, growing degree days are accrued. A threshold temperature of 5°C is generally used for forage crops and canola. For more information about the source data and figures, click here.

Cumulative degree-days above 0°C are calculated by adding average daily temperature over a defined time period (e.g. a year or month) for those days when the mean temperature exceeds 0°C. This index can be used as an indicator for plant and insect growth.  The warmer the weather, the more quickly these species develop, and the cooler the temperature, the slower they develop. For more information about the source data and figures, click here.

Heating degree days give an indication of the amount of space heating that may be required to maintain comfortable conditions in a building during cooler months. A threshold temperature of 18°C is used and for any day when the mean temperature is below this value, heating degree days are accrued. So, if the daily mean temperature on a given day is 10°C, then 8 HDDs are accrued for this day. HDD values are totalled over the year; the larger the HDD value the greater the requirement for space heating. For more information about the source data and figures, click here.

This is the number of days when the daily maximum temperature does not exceed 0°C. For more information about the source data and figures, click here.

The number of tropical nights refers to the number of days when the minimum temperature (which usually refers to night-time temperature) value does not go below 18°C. For more information about the source data and figures, click here.

The number of tropical nights refers to the number of days when the minimum temperature (which usually refers to night-time temperature) value does not go below 20°C. For more information about the source data and figures, click here.

The number of tropical nights refers to the number of days when the minimum temperature (which usually refers to night-time temperature) value does not go below 22°C. For more information about the source data and figures, click here.

Intensity Duration Frequency (IDF) curves relate short-duration rainfall intensity with its frequency of occurrence and are often used for flood forecasting and urban drainage design.

As most people have experienced, a very intense storm can bring lots of rain over a very short period of time, overwhelming storm drains, flooding basements, and washing out bridges and roads. Therefore, when engineers and hydrologists are designing safe and reliable infrastructure, they need to know how often these damaging rainstorms occur.

One way to determine this is to use Historical Rainfall Intensity-Duration-Frequency (IDF) Curves. Historical IDF Curves show the frequency (probability of occurrence) of extreme rainfall rates persisting for short periods of time (5, 10, 15, 30, 60 min; 2, 6, 12, and 24 h) based on historical rainfall data recorded at a specific weather station. They do not reflect rainfall amounts or rates over wider areas such as entire cities or river basins. The curves are produced to support the development of infrastructure capable of handling extreme rainfall events thereby reducing the risk of flooding and the associated damage to property, and risk to people. IDF Curves are most often used by professional groups such as: engineers, water resource managers, urban and regional planners.

Use with caution: Historical IDF Curves alone cannot be used to assess future extreme rainfall. Since IDF Curves are based on the analysis of historical rate-of-rainfall data, they do not explicitly incorporate any projected future trends due to a changing climate. 

Due to the sparsity of sub-daily hourly or minute-by-minute rainfall observations and the high levels of uncertainty associated with future projections of extreme rainfall at a specific location and over short time periods high spatial and temporal resolution, Environment and Climate Change Canada does not produce future IDF curves.

For further technical information on how IDF Curves are produced, please refer to Environment and Climate Change Canada’s Engineering Climate Datasets page or contact the Engineering Climate Services Unit at [email protected].

Climate Normals 1981-2010 are used to summarize or describe the average climatic conditions of a particular location. At the completion of each decade, Environment and Climate Change Canada updates its climate normals for as many locations and as many climatic characteristics as possible. The climate normals offered here are based on Canadian climate stations with at least 15 years of data between 1981 to 2010.