Current Climate and Observed Trends
The world has increasingly been concerned with the changes in our climate due largely to adverse impacts being seen not just globally, but also in regional, national and even, local scales. In 1988, the United Nations established the IPCC to evaluate the risks of climate change and provide objective information to governments and various communities such as the academe, research organizations, private sector, etc. The IPCC has successively done and published its scientific assessment reports on climate change, the first of which was released in 1990. These reports constitute consensus documents produced by numerous lead authors, contributing authors and review experts representing Country Parties of the UNFCCC, including invited eminent scientists in the field from all over the globe.
In 2007, the IPCC made its strongest statement yet on climate change in its Fourth Assessment Report (AR4), when it concluded that the warming of the climate system is unequivocal, and that most of the warming during the last 50 years or so (e.g., since the mid-20th century) is due to the observed increase in greenhouse gas concentrations from human activities. It is also very likely that changes in the global climate system will continue into the future, and that these will be larger than those seen in our recent past (IPCC, 2007a).
Fig.4 shows the 0.74 C increase in global mean temperature during the last 150 years compared with the 1961-1990 global average. It is the steep increase in temperature since the mid-20th century that is causing worldwide concern, particularly in terms of increasing vulnerability of poor developing countries, like the Philippines, to adverse impacts of even incremental changes in temperatures.
In 2007, the IPCC made its strongest statement yet on climate change in its Fourth Assessment Report (AR4), when it concluded that the warming of the climate system is unequivocal, and that most of the warming during the last 50 years or so (e.g., since the mid-20th century) is due to the observed increase in greenhouse gas concentrations from human activities. It is also very likely that changes in the global climate system will continue into the future, and that these will be larger than those seen in our recent past (IPCC, 2007a).
Fig.4 shows the 0.74 C increase in global mean temperature during the last 150 years compared with the 1961-1990 global average. It is the steep increase in temperature since the mid-20th century that is causing worldwide concern, particularly in terms of increasing vulnerability of poor developing countries, like the Philippines, to adverse impacts of even incremental changes in temperatures.
The IPCC AR4 further states that the substantial body of evidence that support this most recent warming includes rising surface temperature, sea level rise and decrease in snow cover in the Northern Hemisphere (shown in Fig.5).
Additionally, there have been changes in extreme events globally and these include;
- widespread changes in extreme temperatures observed;
- cold days, cold nights and frost becoming less frequent;
- hot days, hot nights and heat waves becoming more frequent; and
- observational evidence for an increase of intense tropical cyclone activity in the North Atlantic since about 1970, correlated with increases of tropical sea surface temperatures (SSTs).
Current climate trends in the Philippines
The rates of increases or decreases in the trends are point values (i.e., specific values in the synoptic weather stations only)
and are available at PAGASA, if needed.
SOURCES: http://kidlat.pagasa.dost.gov.ph/cab/climate_change/CurrentClimateTrends.html