To put the record straight, the concept first came to global consciousness in the 19th century when ice ages and other natural changes were noticed in some parts of the world.
Simply put, climate change is a variation in the statistical distribution of weather patterns when that change lasts for an extended period of time.
It may also refer to a change in average weather conditions, or in the time variation of weather within the context of longer-term average conditions.
Climate change is caused by factors such as biotic processes, variations in solar radiation received by Earth, plate tectonics, and volcanic eruptions.
Global response to climate change
To address the problem of climate change, an international environmental treaty, United Nations Framework Convention on Climate Change (UNFCCC) was adopted on May 9, 1992 and opened for signature at the June 1992 Earth Summit in Rio de Janeiro, Brazil.
It became operational on March 21, 1994, after a sufficient number of countries had ratified it. The UNFCCC objective is to “stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.”
The framework sets non- binding limits on greenhouse gas emissions for individual countries and contains no enforcement mechanisms. Instead, the framework outlines how specific international treaties (called “protocols” or “Agreements”) may be negotiated to specify further action towards the objective of the UNFCCC.
To ensure effectiveness of UNFCCC, the annual conferences on climate change, United Nations Climate Change Conferences (UNCCC) commenced sitting in 1995.
They serve as the formal meeting of the UNFCCC Parties (Conference of the Parties, COP) to assess progress in dealing with climate change.
The first UN Climate Change Conference took place in 1995 in Berlin, Germany and the last one was held in July 2018 in Katowice, Poland.
Human activities or nature; what drives climate change?
Climate change is caused by human and natural factors. The human effect is huge and contributed more to the menace. The natural factors include variations in earth’s orbit, variation in ocean circulation and variation in solar radiation.
“Climate change is largely caused by human activities and to some extent natural factors. It presents a serious threat to nature and people.
“Without ambitious mitigation efforts, global temperature rise this century could exceed 4 degrees Celsius above pre-industrial levels, with catastrophic impacts, a lecturer at the Department of Geography, University of Ibadan, Dr. Faith Anyi, said.
“In the last 100 years average global temperature has increased by 0.74°C, rainfall patterns have changed and the frequency of extreme events increased. Change has not been uniform on either a spatial or temporal scale and the range of change, in terms of climate and weather, has also been variable.
“Change in climate has consequences on the biophysical environment such as changes in the start and length of the seasons, glacial retreat, decrease in Arctic sea ice extent and a rise in sea level. These changes have already had an observable impact on biodiversity at the species level, in term of phenology, distribution and populations, and ecosystem level in terms of distribution, composition and function.”
Effects of climate change on lives
Researchers at the National Institute of Oceanography and Marine Research (NIOMR), Victoria Island, Lagos, had claimed that climate change and global warming have profound implications for conservation priorities and approaches.
“There are several impacts of climate change on biodiversity and ecosystem services.
It affects the populations and distributions of species, the composition of ecological communities, and nature’s provision of goods and services – such as food, fuel and clean water. Climate change also compounds other major threats to biodiversity, such as invasive alien species, habitat fragmentation and overexploitation,” a lecturer at the Biological Oceanography unit of NIOMR, Daniel Fakayode, said.
“Climate change have significant impacts on Nigeria’s freshwater and marine aquatic systems and hence on the country’s fisheries and aquaculture. Fisheries and aquaculture are highly vulnerable to changes in weather pattern and the impacts which could be negative or positive, vary from the coastal areas to the drier northern parts of the country. Elevated water temperatures affect fish physiological processes, thereby affecting spawning, survival of the juveniles, recruit into the exploitable phase of population, population size, production and yield. The impacts of increased flooding of the freshwater bodies will be negative through erosion of watershed, destruction of fish feeding and breeding habitats, decrease in primary productivity and alteration of the normal resilience of the aquatic systems, or positive in expansion of aquatic habitats for primary and fish productions especially during the dry season.”
Nigeria, climate change and mitigating efforts
Climate change has negative impact on the global environment. Some of the devastating effects include volcanic eruption, landslide, erosion, flooding, drought and disease outbreaks. These in turn impact on agriculture and threaten food security.
The Nigerian Meteorological Agency (NiMET) had said in a statement earlier in the year that one major effect of climate change in Nigeria is declining agricultural productivity occasioned by irregular and unpredictable farming calendar.
“Climate in Nigeria has shown considerable temporal and spatial shifts in its variability and change.
Extreme climate and weather events (drought, flood, heatwaves and ocean surges) have become more regular.
“The impacts of extreme weather and climate may be gradual but they are destructive to lives and property and negatively impact on the economy. Floods have become a perennial challenge with increasing intensity each year, leaving colossal losses and trauma,” the agency said.
The Federal Government had in 2016 launched several initiatives such as the resuscitation of the depleting Lake Chad, the Ogoni clean-up project and the Great Green Tree Wall project in 11 northern states in the country to mitigate the effects of climate change.