1. Introduction 2. Climate and Weather in Japan 2.1 Japan''s Climate with Large Regional Differences 2.1.1 Japan''s Climate from a Global Perspective 2.1.2 Major Air Masses Affecting the Climate of Japan 2.

1.3 Mean Annual Temperature, Precipitation and Sunshine Duration 2.1.4 Annual Variations in Mean Monthly Temperature and Precipitation 2.2 Seasonal Variations in the Climate of Japan 2.2.1 Main Seasons and Temperature and Precipitation Distributions in Japan 2.2.

2 Winter 2.2.3 Spring 2.2.4 Rainy Season in Early Summer 2.2.5 Midsummer Season 2.2.

6 Autumn Rainy Season 2.2.7 Late Autumn 2.3 Extreme Weather and Teleconnection Patterns 2.3.1 Cold and warm winters 2.3.2 Cool and Hot Summers 3.

Climate Change in Japan since the 20th Century 3.1 Official Meteorological Observation System in Japan 3.1.1 Relocation of JMA Tokyo Meteorological Observatory and Its Effect 3.2 Climate Variations in Japan since the 20th Century 3.2.1 Temperature Variations since the 20th Century 3.2.

2 Precipitation Variations since the 20th Century 3.2.3 Flood Disasters and Climate Change 3.2.3.1 Flood Disasters in Japan and Their Characteristics 3.2.3.

2 Nagasaki Floods (July 1982) 3.2.3.3 West Japan Floods (July 2018) 3.2.3.4 Long-term Trends in Heavy Rainfall Disasters 3.3 Climate Change in the Mega-city Tokyo 3.

3.1 Temperature Variations since the 20th Century 3.3.2 Precipitation Variations since the 20th Century 3.3.3 Aridification of Tokyo Due to Urbanization 3.4 Urban Heat Islands in Tokyo Metropolis 3.4.

1 High-Resolution Temperature Observation System in Tokyo Metropolis 3.4.2 Summer Temperature Distributions in Tokyo 3.4.2.1 High-Density Temperature Observation System in Tokyo Metropolitan Area 3.4.2.

2 Effects of Sea Breeze on Summer Temperature Patterns in Tokyo 3.4.3 Anthropogenic Energy Consumption in Tokyo 3.4.4 Artificial Urban Surfaces in Tokyo 4. Climate Information from Pre-19th Century Data and Documents 4.1 Early Meteorological Observations in the 19th Century 4.1.

1 Early Meteorological Observations in Nagasaki 4.1.1.1 Japan''s Earliest Meteorological Observations in the 18th Century 4.1.1.2 Meteorological Observations by Dutch Medical Doctors in the 19th Century 4.1.

2 Early Meteorological Observations in Tokyo and Yokohama 4.1.2.1 Early Meteorological Observations in Tokyo 4.1.2.2 Early Meteorological Observations in Yokohama and Yokosuka 4.1.

2.3 Early Meteorological Observations in Osaka and Kobe 4.1.2.4 Reconstruction of Long-term Temperature Series (1820-2000) for West Japan 4.1.3 Early Meteorological Observations at the Russian Consulate in Hakodate 4.1.

4 Mid-19th Century Temperature Observations by a Merchant of the Mito Domain 4.1.5 Meteorological Observations in Naha (Okinawa) in the Mid-19th Century 4.1.6 Lighthouse Meteorological Observations in Japan 4.2 Diary Weather Records since the 17th Century 4.2.1 Location and Duration of Diary Weather Records 4.

2.2 Weather Records of the Two-Century Hirosaki Doman Diary and the Database Thereof 4.2.3 Historical Weather Database (HWDB) 4.3 Long-term Records of Lake Ice Freeze-up/Break-up Dates 4.3.1 Records of Freeze-up and Ice Pressure Ridge at Lake Suwa since 1444 4.3.

2 Records of Ice Freeze-up/Break-up at Lake Jusan during 1705-1860 5. Climate Reconstructions for Historical Periods 5.1 Attempts to Reconstruct Typhoon Tracks and Intensity from Early Weather and Meteorological Records 5.1.1 Reconstruction of the 1882 Typhoon Weather Map Using Lighthouse Observation Data 5.1.2 Reconstruction of the Intensity and Track of the 1828 Siebold Typhoon 5.1.

2.1 Siebold Incident 5.1.2.2 Meteorological Observation by von Siebold 5.1.2.3 Changes in the Air Pressure Before and After the Typhoon Landfall 5.

1.2.4 Reconstruction of the Siebold Typhoon Track 5.1.3 Variability of Typhoons that Hit Japan after the Mid-19th Century 5.2 Climate Reconstructions from Diary Weather Records since the 18th Century 5.2.1 Winter Temperature Reconstruction Based on the Snowfall Ratio Obtained from Diary Weather Records 5.

2.2 Winter Monsoon Climate Reconstructions from the 1840s-1850s Based on Early Meteorological Data and Historical Documentary Records 5.2.3 Summer Temperature Variations Reconstructed from Precipitation Frequency: The Cases of Tokyo and Hiroshima 5.2.3.1 Tokyo: 1721-2020 5.2.

3.2 Hiroshima: 1779-2015 5.2.4 Meteorological Disasters from the 17th to 19th century 5.2.4.1 Storm Disasters and Great Famines in Summer 5.2.

4.2 Heavy Snowfall in Edo (Tokyo) 5.2.5 Great Famines and Climate Change in the 1780s 5.3 Climate Reconstruction from Records of Full-flowering Dates for Cherry Trees over the Past 1,200 Years 5.4 Climate Reconstructions from Pollen in the Highland Moors in Central Japan over the Past 7600 Years 6. Conclusions.