1. Introduction
Climate change (CC) poses significant threats to agricultural production and adequate climate change information can help farmer to adapt to this [
1,
2]. This information is especially important in developing countries where agriculture is characterized by small holder and subsistence farmers [
3]. Availability of accurate climate information will enhance the resilience among farmers to cope with the posed challenging conditions [
4]. In addition, Paavola [
5] observes that since climate change mostly affects vulnerable communities, there is a need to explore farmers’ perceptions on climate change. Hereafter, actual perception on the same will be of use for improving agricultural production and environmental conservation in various agro-ecological zones. In addition, future precipitation projections from CMIP-3 and CMIP-5 models further suggest that towards the end of the twenty-first century, the eastern African region will experience inadequate wetter rainy seasons and thus, agriculture will be impacted negatively [
6].
Most farmers perceive rainfall and temperatures as significant aspects of climate, since the two variables have profound and immediate impacts on their livelihoods and environment [
3,
7]. With them, the increase in drought extreme incidences is generally perceived as bad years. Several studies show that farmers can easily identify the changing climate through crop yields [
4,
8,
9,
10]. The prevalence of more bad years has negatively impacted farmers’ livelihoods, thus affecting baseline vulnerabilities [
5,
11]. Despite the slight difference that may exist against the scientific point of view, the farmers’ perception is rather reflected in the report by Intergovernmental Panel on Climate Change (IPCC) [
12] that reveals that rainfall variations in terms of amount, frequency, inter-annual variability, onset, cessation or/and the shrinkage of the growing season are key indicators perceived by the farmers that climate is changing. Although the farmers’ perception on climate change may differ between local and global levels, between communities and between climatic regions [
7,
13], Paavola [
5] and Kilembe et al. [
14] point out that farmers’ perception are crucial when proposing adaptation plans or mitigation measures that would help farmers to cope or/and decrease their vulnerability to such environmental stresses.
So far, there is substantial literature examining the effects of climate change in Tanzania. Studies by Ahmed et al. [
4], Rowhani et al. [
8], Lobell and Burke [
15], and Lobell et al. [
16] are among the dominant studies that established climate knowledge based on climate models, statistical crop models, and economic simulations to determine climate vulnerability among the smallholder farmers between the late 20th century and early 21st century. Rowhani et al. [
8] specified that a 20% increase in intra-seasonal precipitation variability reduces agricultural yields by 4.2%, 7.2%, and 7.6% for maize, sorghum, and rice respectively, which are the major food crops in Tanzania. The study further projected that by 2050 climate change and variability will stress crop yields in Tanzania by 3.6%, 8.9%, and 28.6% for maize, sorghum, and rice respectively. These studies with others such as Paavola [
5] Mongi et al. [
10], Kilembe et al. [
14], Lobell et al. [
16], Msongaleli et al. [
17], and Mkonda [
18] confirmed the decreasing rainfall in various parts of Tanzania, and insisted that this scenario has significant implications to crop yields. This was further supported in recent studies by Below et al. [
7], Sieber et al. [
13], FAO [
19], Kangalawe [
20] and Cooper and Wheeler [
21].
In addition, Lobell et al. [
16], and the Food and Agricultural Organization of the United Nations [
19] further emphasized that rain-fed agriculture will be more susceptible to any further variation in climate. Similarly, Challinor et al. [
1] established that climate change and variability has significantly affected staple food crops especially cereals like maize, rice, sorghum and millet. In addition, Challinor et al. [
1], Adger [
3], Paavola [
5], Kangalawe [
20], and Kangalawe and Lyimo [
21] assert that the increase in drought incidences has increased the level of vulnerability among the farmers in most sub-Sahara Africa because their livelihoods depend entirely on rain-fed agriculture. Spatially, this vulnerability is more pronounced in semi-arid areas because of prolonged excessive droughts being mainly attributed to unreliable and erratic rainfall, very low mean annual rainfall, and quite unpredictable onset and cessation rains [
1,
14,
22,
23,
24,
25,
26,
27,
28,
29,
30,
31,
32,
33,
34,
35,
36].
In terms of policy reflection, the National Adaptation Plan of Action and Tanzania’s National Strategy for Growth and Reduction of Poverty identified droughts and floods as among the primary threats to agricultural productivity and poverty vulnerability in the country [
23,
24,
25]. According to Tanzanian context, climate change issues are addressed in various sectoral policies i.e., all ministries related to environment have policies that address the same. Among others are the Agriculture and Livestock Policy of 2013, National Environmental Policy of 1997, National Forestry Policy of 1998, National Tourism Policy of 1999, and the Agricultural Sector Development Program of 2002 [
26]. However, our interest is in the Agricultural Sector which is a lead Ministry in this category [
23].
Tanzania agricultural policy aims at increasing food security levels in the country through increased crop production [
23]. In response to climate change, the policy has emphasized the use of drought resistant crops, increased irrigation and soil fertilization, but this has not yet been fruitful. It actually realizes that rainfed agriculture is no longer a good proposition for crop production in the country. In this regard, different adaptation strategies such as early farming, planting short maturing crops, and diversification to other economic sectors have been equally estipulate in the policy. On the other hand, the policy attracts large scale investment (intensive agriculture) in agriculture to maximize the production levels and curb food insecurity in various agro-ecological zones of the country.
The agricultural sector in Tanzania is a spearhead economic sector in the country (serving over 70% livelihoods), thus the policy has taken some precautions that reduce the vulnerability of smallholder farmers from climate change impacts. For collective implementations, the government introduced a number of initiatives and programs to spearhead the agriculture sector. The Agriculture Sector Development Program (ASDP) was introduced in the 2000s to speed up crop production in the country. Similarly, the “Kilimo Kwanza” (Agriculture First in English) initiative which was introduced in 2009, aimed to hasten the production of the agricultural sector and its allied sectors. The ASDP aims to enable farmers to have better access to and use of agricultural knowledge, technologies, and market infrastructure; all of these contribute to higher productivity, profitability, and farm incomes within the era of a changing climate, under a Local Level Component and a National Level Component. It is mainly implemented by Local Government Authorities based on District Agricultural Development Plans as part of the broader District Development Plans. Thereby, the initiatives and programs are there to facilitate the achievement of the Tanzania Development Vision of 2025, especially in this era of global climate change [
26,
27].
Since farmers’ perceptions are mainly based on the impacts of CC on their livelihoods, this study has also touched on the major adaptation strategies adopted by the farmers in the process of reducing their vulnerability to CC [
23,
24,
25,
36]. The existing adaptation strategies may inform much about the farmers’ knowledge on these adaptation strategies. In general, the adoption of climate smart-agriculture (CSA) practices is highly recommended by various studies as an adaptation strategy to CC impacts [
20,
21,
22,
23,
24]. The CSA includes, but is limited to, conservation agriculture, irrigation, and the use of drought resistant crop cultivars [
32,
33,
34,
35]. Kimaro et al. [
31] recommends the use of CSA practices as a strategy to optimize yields under the auspice of climate stress along the Eastern Arc Mountains of Tanzania; however, most of these practices have not yet met the required demand of farmers in the area, thus far, much efforts should be done to make CSA beneficial and sustainable from local to national level.
Although the science of detecting, attributing changes in the climate impacts and developing projections for future changes is progressing rapidly, there has been little systematic evaluation of farmers’ perception to climate change as associated with meteorological analyses and policy implications in Tanzania. The establishment of this aspect will be a robust step to building resilient livelihoods, an adaptive capacity for climate change, and variability through the adoption of climate smart agriculture that is endorsed by sound policies and tools. Thus, it was worthwhile to ascertain climate information basing on farmers’ perception and experiences (indigenous knowledge), meteorological data and assess the policy responses for the benefits to farmers.
The main impetus of this empirical study was to assess farmers’ perception on climate change in the Kongwa District, the semi-arid area of Central Tanzania, analyze rainfall and temperature data from Tanzania Meteorological Station (TMA) and meteorological stations in the study area e.g., Kinyasungwe meteorological station, and finally, assess policy implications on the same.
4. Discussion
The present study has confirmed that real rainfall and temperature are changing. The results in
Figure 3 shows that more than 50% of the respondents mentioned rainfall as the main aspect of climate, exceeding temperature, sunshine, and humidity respectively. This reflects how rainfall variability is understood and affects people’s livelihoods in the area. Rainfall variability has been affecting the onset and cessation, thus upsetting the farming calendar in the area. The results from meteorological data analyses and farmers’ perception with regards to policy review supports this assertion (
Figure 2,
Figure 3,
Figure 4,
Figure 5,
Figure 6 and
Figure 7, and
Table 2 and
Table 3). The farmers’ responses in
Figure 2,
Figure 3 and
Figure 4 indicated the farmers’ awareness on the changing climate and more especially on the increasing frequency of droughts extremes in the area.
Besides, the results showed that 60% of the farmers were assertive that the mean annual temperature has been increasing, while 30%, 7%, and 3% assumed that it has been fluctuating, decreasing, and no change respectively (
Figure 4), while 80% said that the mean temperature during the growing season has been increasing (
Table 2). This response was related to the changes in temperature on annual basis. They also confirmed that rainfall has generally been decreasing. These results were in agreement with Ahmed et al. [
4], Below et al. [
7] and Rowhani et al. [
8]. They additionally argued that rain onset and cessation have been too unpredictable, which have been affecting their farming calendar. They also reported that, in the recent years, there has been shrinkage of long rains which used to appear from around November to April, but now prevailing from around January to March. This has posed significant impacts to the major livelihoods of the people.
Further, the farmers noticed that the overall climate has been changing, even though they did not give any quantification of the change (
Figure 4). These climatic turbulences disturbed the agricultural systems, ecology and ecosystems of the area. About 60% of the respondents who asserted rains to have been decreasing during the growing season, also informed that there have been increased incidences of droughts extremes. This verdict is in agreement with Ahmed et al. [
4], Below et al. [
7], and Rowhani et al. [
8] who found that more than 50% of the respondents asserted on decreasing rains. Despite the increasing change of farming systems and less dependence on farming, most rural people in Tanzania and Africa are still vulnerable to climate change [
13,
36]. To reduce the vulnerability, farmers have been adopting some adaptation measures like early planting and planting drought tolerant crops to adjust to the stress; however, the level of rural peoples’ vulnerability is considerably high. Consequently, by stipulating in the policies that climate change impacts should be adapted, agricultural and other sectoral policies have adhered to the reality that climate is changing [
24,
25].
In Ugogoni village, the farmers asserted that for the past ten years there has been an increased shrinkage of the growing season. They further clarified that formerly the growing season had about five months commencing from December to April, but in recent times, this duration had decreased to three or two months. This shrinkage has confirmed the disappearance of short rains which previously used to appear around October to December. Meanwhile, the farmers in Mnyakongo village acknowledged that in some years there had been high rainfall; however with fewer wet spells and thus far, bringing little crop yield. This was in agreement with meteorological analyses where high rainfall can be recorded but with either fewer or unevenly distributed wet spells (
Figure 6). In most cases, the area had been receiving fewer wet spells that were insufficient for agricultural production.
Given that smallholder farming is the most vulnerable livelihood in the area and most of sub-Saharan Africa [
2], to reduce this vulnerability, Paavola [
5] and Sovacool et al. [
11] accentuate that local adaption strategies such as early planting should be emphasized by agricultural and extension officers, in order to increase resilience and quick recovery from climate change impacts. These officers are responsible for the planning and implementation of agricultural programs in their locality.
During extreme food shortage, most farmers cope by reducing the number of daily meals, and eating some wild fruits “
ubuyu” (fruits from Baobab tree), which are common wild fruits in the area. In addition, climate smart agriculture has been adopted by some farmers in the area to adapt to climate impacts.
Table 3 shows the existing adaptation measures (mainly climate smart agriculture) in the area, however, the adaptive capacity of each household is based on the level of resource endowments [
1]. In this aspect, the poor have a weak capacity to cope compared to the middle and upper classes. These results of the present study are in agreement with Ahmed et al. [
4] Below et al. [
7], Rowhani et al. [
8], Sieber et al. [
13], Msongaleli et al. [
17], and Cooper and Wheeler [
22]. Despite little achievement in these adaptation strategies, much more should be done to improve the situation, as proposed by the respondents themselves in
Table 4. They proposed these recommendations to the government because the majority of them had limited knowledge on the agricultural policy, and what has been stipulated in it.
Therefore, farmers’ responses can be interpreted as knowledge that needs specific guidance from the governing policy, so that adaptation and mitigation measures can be definite and strong [
32,
33,
34,
35]. In this case, scientific analyses and climate modeling need to support the creation of farmers’ awareness towards the same, otherwise, uncertainties may arise. So far, these uncertainties affect production systems and eventually cause frequent poor yields, food insecurity, and abject poverty in the community.
Besides, the results from meteorological data analyses (
Figure 5,
Figure 6 and
Figure 7) revealed that there has been a temporal fluctuation and change of both rainfall and temperature. Mean annual and monthly rainfall have been fluctuating at a decreasing trend (
Figure 5 and
Figure 6), while mean annual and monthly temperature have been fluctuating at an increasing trend (
Figure 7). The number of wet spells during the growing seasons appeared to have decreased significantly (
Figure 6). January (
Figure 6a) had a high intensity of fluctuation and decreased significantly compared to February and March as seen in
Figure 6b,c.
These results are in agreement with those by Challinor et al. [
1], Rowhani et al. [
8] and Mkonda [
18]. These authors confirmed that the more the wet spells, the higher the yields, and the fewer the wet spells, the more meager the yields. The number of wet spells are perceived by farmers as a good climatic moment, since these wet spells have implications on crop production [
4]. In this aspect, we needed to be a bit skeptical because there can numerous wet spells from low rainfall or few wet spells from high rainfall [
5]. This is because we mostly look at cumulative rains. According to the analyses of farmers’ perception, it was found that at least 10 (i.e., numerous) wet spells that are evenly distributed within a month, have significant impacts to crop production as they provide continued moisture in the soils.
On the other hand, January and March experienced high temperature variations (
Figure 7a,c) compared to February (
Figure 7b). This had negative implications to crop yields because in most cases, high temperature lowers crop yields and vice versa. This is mostly applied to maize, sorghum, and millet which are not strongly heat resistant crops.
Comparatively, the trends of rainfall in
Figure 5 and
Figure 6 and temperature presented in
Figure 7 are in agreement with other scholars’ findings like Paavola [
5] and Rowhani et al. [
8], who proclaimed that the overall rainfall variability is operating with a decreasing trend, while temperature is increasing. Rowhani et al. [
8] further predicted that temperature would increase by 2 °C and 4 °C by 2050 and 2100 respectively. He concluded that this trend would exacerbate negative impacts to already stressed human livelihoods and biodiversity. Other supporting scholars with similar observations include Ahmed et al. [
4], Rowhani et al. [
8], Mongi et al. [
10], Mkonda [
18], Kangalawe [
20], Kangalawe and Lyimo [
21], Yanda [
28], and Birkmann et al. [
29], just to mention a few.
Basing on the two sources of information i.e., farmers’ perceptions and meteorological data, we can confidently conclude that rainfall and temperature are changing in Tanzanian. This is because the two sources presented similar results (liaisons). Both showed that rainfall is generally decreasing, especially by observing at drought extremes incidences while temperature is increasing. This reality was proved through field physical observations, as the level of drought in the area was severe. In addition, different models such as Atmosphere-Ocean General Circulation Models (AOGCMs) and CMIP-3 and CMIP-5 have depicted the same trend. Thus, for sustainable adaptation to climate change impacts, we have to validate the information from these two sources and develop an adaptation plan that can increase resilience to the destitute.
While the exact realization of the climate system over the next two decades is unknown, the poverty results from the overall CMIP3 GCM ensemble suggest slightly increasing poverty vulnerability in Tanzania [
4]. This is because climate models sometimes indicate less impact, while in actual sense the situation is worse on the ground. This climate-based uncertainty can potentially be resolved by developing the decadal-scale climate prediction techniques [
30]. In whole, the determination of climate change should be featured into a sound policy that should stipulate, emphasize and ensure the implementation of climate smart agriculture especially to rural farmers.
However, under some context, there has been a differing perspective between the farmers and the Tanzania Meteorological Agency. In some aspects, the meteorological authorities has been reporting increased rainfall during some years, while the farmers in the fields do not feel the same. In this context, further speculations revealed that the number of drought extremes had outnumbered the wet ones, and thus, having high total rainfall with insignificant impact on farms/production systems. The impacts of this variation has been coupled by the great variability of onset and cessation of rains. This also has been affecting the farming calendar. So far, this has been affecting significantly the poor people who are more vulnerable to the situation [
13,
30].
On policy implications; agricultural policy, various agricultural programs and projects have realized that climate impacts have significant effects to crop production. In a country where 70% of agriculture industry is dominated by smallholder farmers, the improvement of adaptation is strategies is quite pretty. However, the Agricultural Policy (i.e., main agricultural documents) has lightly stipulated climate issues. Therefore, the scientific findings and indigenous/precipitation knowledge should be helpful in amending or improving the related policies.